Jul. 2013 - Now: Research Associate, Centre for Clean Energy Technology, School of Mathematical and Physical Science, University of Technology, Sydney
Jul. 2012 - Jul. 2013: Research assistant, Centre for Clean Energy Technology, School of Chemistry and Forensic Science, University of Technology, Sydney
Aug. 2010 - Nov. 2012: Centre for Clean Energy Technology, School of Chemistry and Forensic Science, University of Technology, Sydney (PhD Conferred 22 Nov. 2012)
Jun. 2008 - Jul. 2010: Faculty of Engineering, University of Wollongong. (PhD candidate)
Sep. 2005 - Jul. 2007: Department of Applied Chemistry, Harbin Institute of Technology, China. (M. E.)
Sep. 2001 - Jul. 2005: Department of Applied Chemistry, Harbin Institute of Technology, China. (B. E.)
Can supervise: YES
Dr. Bing Sun, is an early career researcher in the fields of materials science, electrochemistry and energy storage. He has interests in the synthesis of nanostructured materials and their applications in the fields of lithium oxygen batteries, lithium ion batteries, lithium sulfur batteries, supercapacitors and gas sensors. During the past few years, he has developed the synthesis and applications for one-dimensional, mesoporous, and novel core-shell structure materials. The results have been published in peer-reviewed journals, such as Advanced Materials, Nano Letters, Scientific Reports, Nano Research, Advanced Energy Materials, Carbon, Journal of Physical Chemistry C, Chemistry - A European Journal, Journal of Materials Chemistry A, Electrochemistry Communications, and Journal of Power Sources. So far, he has published 52 papers and 1 book chapter. His work has been cited more than 2290 times, with an h-index of 27.
Sun, B, Zhang, Q, Xiang, H, Han, F, Tang, W, Yuan, G, Cong, Y, Fan, C, Westwood, A & Li, X 2020, 'Enhanced active sulfur in soft carbon via synergistic doping effect for ultra–stable lithium–ion batteries', Energy Storage Materials, vol. 24, pp. 450-457.View/Download from: Publisher's site
© 2019 The formation of C–S bonds with high activity in a carbon skeleton is considered to be one of the most effective strategies to facilitate highly reversible alkali storage reactions. In this work, by the combination of heteroatomic control and structural design, N, P and S ternary–doped hierarchical porous soft carbon (NPSC) is obtained with a high concentration of C–S bonds, large specific surface area and large graphitic interlayer spacing. As anode materials for lithium–ion batteries (LIBs), NPSC exhibits a reversible capacity of 500 mA h g−1 and 90% capacity retention can be realized at 500 mA g−1 after 500 cycles, showing its high–rate capability and long–term cyclability. In addition, a full cell based on a LiVPO4F cathode and an NPSC anode delivers high discharge capacity and superior cycling stability. This high performance is attributed to the introduction of P, which promotes the utilization of S through the formation of C–S bonds. In addition, the synergistic doping effect increases the interlayer spacing, facilitating rapid interfacial Li+ adsorption and diffusion reactions. This strategy provides an efficient route toward excellent heteroatom–doped carbon for energy storage and conversion applications.
Potassium metal batteries are considered as attractive alternatives beyond lithium-ion batteries. However, uncontrollable dendrite growth on the potassium metal anode has restrained their practical applications. A high-performance potassium anode achieved by confining potassium metal into a titanium-deficient nitrogen-containing MXene/carbon nanotube freestanding scaffold is reported. The high electronic transport and fast potassium diffusion in this scaffold enable reduced local current density and homogeneous ionic flux during plating/stripping processes. Furthermore, as verified by theoretical calculations and experimental investigations, such "potassium-philic" MXene sheets can induce the nucleation of potassium, and guide potassium to uniformly distribute in the scaffold upon cycling. Consequently, the as-developed potassium metal anodes exhibit a dendrite-free morphology with high Coulombic efficiency and long cycle life during plating/stripping processes. Such anodes also deliver significantly improved electrochemical performances in potassium-sulfur batteries compared with bare potassium metal anodes. This work can provide a new avenue for developing potassium metal-based batteries.
Xiong, P, Zhang, F, Zhang, X, Wang, S, Liu, H, Sun, B, Zhang, J, Sun, Y, Ma, R, Bando, Y, Zhou, C, Liu, Z, Sasaki, T & Wang, G 2020, 'Strain engineering of two-dimensional multilayered heterostructures for beyond-lithium-based rechargeable batteries', NATURE COMMUNICATIONS, vol. 11, no. 1.View/Download from: Publisher's site
Yu, X, Yu, Z-Y, Zhang, X-L, Li, P, Sun, B, Gao, X, Yan, K, Liu, H, Duan, Y, Gao, M-R, Wang, G & Yu, S-H 2020, 'Highly disordered cobalt oxide nanostructure induced by sulfur incorporation for efficient overall water splitting', NANO ENERGY, vol. 71.View/Download from: Publisher's site
Fan, L, Zhang, Y, Guo, Z, Sun, B, Tian, D, Feng, Y, Zhang, N & Sun, K 2020, 'Hierarchical Mn3O4 Anchored on 3D Graphene Aerogels via C−O−Mn Linkage with Superior Electrochemical Performance for Flexible Asymmetric Supercapacitor', Chemistry: A European Journal.View/Download from: Publisher's site
© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Flexible asymmetric supercapacitors are more appealing in flexible electronics because of high power density, wide cell voltage, and higher energy density than symmetric supercapacitors in aqueous electrolyte. In virtues of excellent conductivity, rich porous structure and interconnected honeycomb structure, three dimensional graphene aerogels show great potential as electrode in asymmetric supercapacitors. However, graphene aerogels are rarely used in flexible asymmetric supercapacitors because of easily re-stacking of graphene sheets, resulting in low electrochemical activity. Herein, flower-like hierarchical Mn3O4 and carbon nanohorns are incorporated into three dimensional graphene aerogels to restrain the stack of graphene sheets, and are applied as the positive and negative electrode for asymmetric supercapacitors devices, respectively. Besides, a strong chemical coupling between Mn3O4 and graphene via the C-O-Mn linkage is constructed and can provide a good electron-transport pathway during cycles. Consequently, the asymmetric supercapacitor device shows high rate cycle stability (87.8 % after 5000 cycles) and achieves a high energy density of 17.4 μWh cm−2 with power density of 14.1 mW cm−2 (156.7 mW cm−3) at 1.4 V.
Li, M, Sun, B, Ao, Z, An, T & Wang, G 2020, 'Atomic-scale identification of influencing factors of sodium dendrite growth on different current collectors', JOURNAL OF MATERIALS CHEMISTRY A, vol. 8, no. 20, pp. 10199-10205.View/Download from: Publisher's site
Tkacheva, A, Zhang, J, Sun, B, Zhou, D, Wang, G & McDonagh, AM 2020, 'TEMPO-Ionic Liquids as Redox Mediators and Solvents for Li-O-2 Batteries', JOURNAL OF PHYSICAL CHEMISTRY C, vol. 124, no. 9, pp. 5087-5092.View/Download from: Publisher's site
Xiong, P, Sun, B, Sakai, N, Ma, R, Sasaki, T, Wang, S, Zhang, J & Wang, G 2020, '2D Superlattices for Efficient Energy Storage and Conversion.', Advanced Materials, pp. e1902654-e1902654.View/Download from: Publisher's site
2D genuine unilamellar nanosheets, that are, the elementary building blocks of their layered parent crystals, have gained increasing attention, owing to their unique physical and chemical properties, and 2D features. In parallel with the great efforts to isolate these atomic-thin crystals, a unique strategy to integrate them into 2D vertically stacked heterostuctures has enabled many functional applications. In particular, such 2D heterostructures have recently exhibited numerous exciting electrochemical performances for energy storage and conversion, especially the molecular-scale heteroassembled superlattices using diverse 2D unilamellar nanosheets as building blocks. Herein, the research progress in scalable synthesis of 2D superlattices with an emphasis on a facile solution-phase flocculation method is summarized. A particular focus is brought to the advantages of these 2D superlattices in applications of supercapacitors, rechargeable batteries, and water-splitting catalysis. The challenges and perspectives on this promising field are also outlined.
Yan, K, Zhao, S, Zhang, J, Safaei, J, Yu, X, Wang, T, Wang, S, Sun, B & Wang, G 2020, 'Dendrite-Free Sodium Metal Batteries Enabled by the Release of Contact Strain on Flexible and Sodiophilic Matrix.', Nano letters.View/Download from: Publisher's site
The formation of sodium (Na) dendrites during cycling has impeded the practical application of Na metal anodes. Herein, we developed a flexible graphene-based matrix, e.g., a porous reduced graphene oxide (PRGO) film, to support dendrite-free Na nucleation and plating, contributing to high-performance Na metal batteries. The PRGO film possessed outstanding merits of sodiophilicity and flexibility. The sodiophilic PRGO film enabled uniform Na nucleation in the initial electroplating stage. Furthermore, the flexible PRGO film with a small Young's modulus effectively alleviated the texture deformation of electrodeposited Na, leading to a compact and dendrite-free Na deposition layer. The well-maintained Na metal anodes on the PRGO film exhibited superior cyclability, high Coulombic efficiency, and improved energy density in both half-cell and full-cell testing. This work illustrates the great significance of mechanical properties of the supporting matrix for the Na electroplating, which provides a new strategy to develop high-performance dendrite-free Na metal batteries.
Yin, Y, Zhang, Y, Liu, N, Sun, B & Zhang, N 2020, 'Biomass-Derived P/N-Co-Doped Carbon Nanosheets Encapsulate Cu3P Nanoparticles as High-Performance Anode Materials for Sodium–Ion Batteries', Frontiers in Chemistry, vol. 8.View/Download from: Publisher's site
© Copyright © 2020 Yin, Zhang, Liu, Sun and Zhang. Biomass-derived approaches have been accepted as a practical way for the design of transitional metal phosphides confined by carbon matrix (TMPs@C) as energy storage materials. Herein, we successfully synthesize P/N-co-doped carbon nanosheets encapsulating Cu3P nanoparticles (Cu3P@P/N-C) by a feasible aqueous reaction followed by a phosphorization procedure using sodium alginate as the biomass carbon source. Cu-alginate hydrogel balls can be squeezed into two-dimensional (2D) nanosheets through a freeze–drying process. Then, Cu3P@P/N-C was obtained after the phosphorization procedure. This rationally designed structure not only improved the kinetics of ion/electron transportation but also buffered the volume expansion of Cu3P nanoparticles during the continuous charge and discharge processes. In addition, the 2D P/N co-doped carbon nanosheets can also serve as a conductive matrix, which can enhance the electronic conductivity of the whole electrode as well as provide rapid channels for electron/ion diffusion. Thus, when applied as anode materials for sodium-ion batteries, it exhibited remarkable cycling stability and rate performance. Prominently, Cu3P@P/N-C demonstrated an outstanding reversible capacity of 209.3 mAh g−1 at 1 A g−1 after 1,000 cycles. Besides, it still maintained a superior specific capacity of 118.2 mAh g−1 after 2,000 cycles, even at a high current density of 5 A g−1.
Zhao, S, Dong, L, Sun, B, Yan, K, Zhang, J, Wan, S, He, F, Munroe, P, Notten, PHL & Wang, G 2020, 'K2 Ti2 O5 @C Microspheres with Enhanced K+ Intercalation Pseudocapacitance Ensuring Fast Potassium Storage and Long-Term Cycling Stability.', Small (Weinheim an der Bergstrasse, Germany), pp. e1906131-e1906131.View/Download from: Publisher's site
Benefiting from the natural abundance and low standard redox potential of potassium, potassium-ion batteries (PIBs) are regarded as one of the most promising alternatives to lithium-ion batteries for low-cost energy storage. However, most PIB electrode materials suffer from sluggish thermodynamic kinetics and dramatic volume expansion during K+ (de)intercalation. Herein, it is reported on carbon-coated K2 Ti2 O5 microspheres (S-KTO@C) synthesized through a facile spray drying method. Taking advantage of both the porous microstructure and carbon coating, S-KTO@C shows excellent rate capability and cycling stability as an anode material for PIBs. Furthermore, the intimate integration of carbon coating through chemical vapor deposition technology significantly enhances the K+ intercalation pseudocapacitive behavior. As a proof of concept, a potassium-ion hybrid capacitor is constructed with the S-KTO@C (battery-type anode material) and the activated carbon (capacitor-type cathode material). The assembled device shows a high energy density, high power density, and excellent capacity retention. This work can pave the way for the development of high-performance potassium-based energy storage devices.
Zhao, S, Yan, K, Zhang, J, Sun, B & Wang, G 2020, 'Reviving Reaction Mechanism of Layered Lithium-Rich Cathode Materials for High-Energy Lithium-Ion Battery.', Angewandte Chemie (International ed. in English).View/Download from: Publisher's site
Layered lithium-rich cathode materials have attracted extensive interests owing to their high theoretical specific capacity (320 - 350 mA h g -1 ). However, poor cycling stability and sluggish reaction kinetics inhibit their practical applications. After many years of quiescence, it is expected to revive the development of layered lithium-rich cathode materials to resolve our increasing dependence on high-energy-density lithium-ion batteries. Herein, we reviewed recent research progresses and in-depth understandings of structure characterizations and reaction mechanisms of layered lithium-rich manganese-based cathode materials. In particular, we comprehensively summarized the proposed reaction mechanisms on both the cationic redox reaction of transition-metal ions and the anionic redox reaction of oxygen species. Finally, we discussed opportunities and challenges facing the future development of LLRM cathode materials for next-generation lithium-ion batteries.
Guo, X, Zhang, J, Zhao, Y, Sun, B, Liu, H & Wang, G 2019, 'Ultrathin Porous NiCo2O4 Nanosheets for Lithium-Oxygen Batteries: An Excellent Performance Deriving from an Enhanced Solution Mechanism', ACS Applied Energy Materials, vol. 2, no. 6, pp. 4215-4223.View/Download from: Publisher's site
© Copyright 2019 American Chemical Society. Lithium-oxygen batteries are of interest for long-range electric vehicles owing to their high theoretical energy density. However, the poor cycling performance and low round-trip efficiency deriving from the sluggish oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) kinetics severely impede their practical application. Ingenious design of cathode catalysts is imperative to overcome these challenges. Here, we report ultrathin porous NiCo2O4 nanosheets with abundant oxygen vaccines as an efficient cathode catalyst toward both OER and ORR for Li-O2 batteries. From combined theoretical calculation with experimental results, a unique enhanced solution mechanism is proposed in the ether-based electrolyte system. Benefiting from the porous 2D architecture of the cathode and the hierarchical toroidal products, the Li-O2 batteries using NiCo2O4 cathodes deliver a high discharge capacity of 16 400 mAh g-1 at 200 mA g-1 and an excellent cycling performance up to 150 cycles with a restricted capacity of 1000 mAh g-1.
Sun, B, Xiong, P, Maitra, U, Langsdorf, D, Yan, K, Wang, C, Janek, J, Schroeder, D & Wang, G 2019, 'Design Strategies to Enable the Efficient Use of Sodium Metal Anodes in High-Energy Batteries', ADVANCED MATERIALS, vol. 32, no. 18.View/Download from: Publisher's site
Tian, H, Shao, H, Chen, Y, Fang, X, Xiong, P, Sun, B, Notten, PHL & Wang, G 2019, 'Ultra-stable sodium metal-iodine batteries enabled by an in-situ solid electrolyte interphase', Nano Energy, vol. 57, pp. 692-702.View/Download from: Publisher's site
© 2018 Elsevier Ltd High capacity sodium (Na) metal anodes open up new opportunities for developing next-generation rechargeable batteries with both high power and high energy densities. However, many challenges still plagued their practical application, including low plating/stripping Coulombic efficiency (CE) and dendrite growth after repeated cycle inducing safety issue. Especially, the sodium metal is less stable in organic (i.e. carbonate-based) electrolytes than lithium metal, due to the more unstable organic solid–electrolyte interface (SEI). Herein, we report a facile technology to stabilize sodium metal anode and inhibit the growth of sodium dendrites. The in-situ ultrathin NaI SEI layer successfully endows best-performance Na/I 2 metal batteries (>2200 cycles) with high capacity (210 mA h g −1 at 0.5 C) based on the conversion reaction chemistry with higher discharge voltage plateau (> 2.7 V) and lower overpotential (134 mV) due to the fast charge transfer dynamics and interfacial stability compared with pristine Na anode. The detailed theoretical calculations and experimental results elucidate that NaI layer has a much lower diffusion barrier compared to that of NaF (NaF as one the most commonly found inorganic components in Na-based SEI layer), and actually facilitates more uniform sodium deposition. This work provides a new avenue for designing low-cost, high-performance and high-safety sodium metal-iodine batteries and other metal-iodine batteries.
Yan, K, Wang, J, Zhao, S, Zhou, D, Sun, B, Cui, Y & Wang, G 2019, 'Temperature-Dependent Nucleation and Growth of Dendrite-Free Lithium Metal Anodes.', Angewandte Chemie (International ed. in English), vol. 58, no. 33, pp. 11364-11368.View/Download from: Publisher's site
It is essential to develop a facile and effective method to enhance the electrochemical performance of lithium metal anodes for building high-energy-density Li-metal based batteries. Herein, we explored the temperature-dependent Li nucleation and growth behavior and constructed a dendrite-free Li metal anode by elevating temperature from room temperature (20 °C) to 60 °C. A series of ex situ and in situ microscopy investigations demonstrate that increasing Li deposition temperature results in large nuclei size, low nucleation density, and compact growth of Li metal. We reveal that the enhanced lithiophilicity and the increased Li-ion diffusion coefficient in aprotic electrolytes at high temperature are essential factors contributing to the dendrite-free Li growth behavior. As anodes in both half cells and full cells, the compact deposited Li with minimized specific surface area delivered high Coulombic efficiencies and long cycling stability at 60 °C.
Yu, X, Yu, Z-Y, Zhang, X-L, Zheng, Y-R, Duan, Y, Gao, Q, Wu, R, Sun, B, Gao, M-R, Wang, G & Yu, S-H 2019, '"Superaerophobic" Nickel Phosphide Nanoarray Catalyst for Efficient Hydrogen Evolution at Ultrahigh Current Densities.', Journal of the American Chemical Society, vol. 141, no. 18, pp. 7537-7543.View/Download from: Publisher's site
The design of highly efficient non-noble-metal electrocatalysts for large-scale hydrogen production remains an ongoing challenge. We report here a Ni2P nanoarray catalyst grown on a commercial Ni foam substrate, which demonstrates an outstanding electrocatalytic activity and stability in basic electrolyte. The high catalytic activity can be attributed to the favorable electron transfer, superior intrinsic activity, and the intimate connection between the nanoarrays and their substrate. Moreover, the unique "superaerophobic" surface feature of the Ni2P nanoarrays enables a remarkable capability to withstand internal and external forces and release the in situ generated H2 bubbles in a timely manner at large current densities (such as >1000 mA cm-2) where the hydrogen evolution becomes vigorous. Our results highlight that an aerophobic structure is essential to catalyze gas evolution for large-scale practical applications.
Zhang, J, Sun, B, Zhao, Y, Tkacheva, A, Liu, Z, Yan, K, Guo, X, McDonagh, AM, Shanmukaraj, D, Wang, C, Rojo, T, Armand, M, Peng, Z & Wang, G 2019, 'A versatile functionalized ionic liquid to boost the solution-mediated performances of lithium-oxygen batteries.', Nature communications, vol. 10, no. 1.View/Download from: Publisher's site
Due to the high theoretical specific energy, the lithium-oxygen battery has been heralded as a promising energy storage system for applications such as electric vehicles. However, its large over-potentials during discharge-charge cycling lead to the formation of side-products, and short cycle life. Herein, we report an ionic liquid bearing the redox active 2,2,6,6-tetramethyl-1-piperidinyloxy moiety, which serves multiple functions as redox mediator, oxygen shuttle, lithium anode protector, as well as electrolyte solvent. The additive contributes a 33-fold increase of the discharge capacity in comparison to a pure ether-based electrolyte and lowers the over-potential to an exceptionally low value of 0.9 V. Meanwhile, its molecule facilitates smooth lithium plating/stripping, and promotes the formation of a stable solid electrolyte interface to suppress side-reactions. Moreover, the proportion of ionic liquid in the electrolyte influences the reaction mechanism, and a high proportion leads to the formation of amorphous lithium peroxide and a long cycling life (> 200 cycles). In particular, it enables an outstanding electrochemical performance when operated in air.
Zhao, S, Yan, K, Munroe, P, Sun, B & Wang, G 2019, 'Construction of Hierarchical K1.39Mn3O6 Spheres via AlF3 Coating for High-Performance Potassium-Ion Batteries', Advanced Energy Materials, vol. 9, no. 10.View/Download from: Publisher's site
© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Potassium-ion batteries are attracting great interest for emerging large-scale energy storage owing to their advantages such as low cost and high operational voltage. However, they are still suffering from poor cycling stability and sluggish thermodynamic kinetics, which inhibits their practical applications. Herein, the synthesis of hierarchical K 1.39 Mn 3 O 6 microspheres as cathode materials for potassium-ion batteries is reported. Additionally, an effective AlF 3 surface coating strategy is applied to further improve the electrochemical performance of K 1.39 Mn 3 O 6 microspheres. The as-synthesized AlF 3 coated K 1.39 Mn 3 O 6 microspheres show a high reversible capacity (about 110 mA h g −1 at 10 mA g −1 ), excellent rate capability, and cycling stability. Galvanostatic intermittent titration technique results demonstrate that the increased diffusion kinetics of potassium-ion insertion and extraction during discharge and charge processes benefit from both the hierarchical sphere structure and surface modification. Furthermore, ex situ X-ray diffraction measurements reveal that the irreversible structure evolution can be significantly mitigated via surface modification. This work sheds light on rational design of high-performance cathode materials for potassium-ion batteries.
Zhou, D, Tkacheva, A, Tang, X, Sun, B, Shanmukaraj, D, Li, P, Zhang, F, Armand, M & Wang, G 2019, 'Stable Conversion Chemistry‐Based Lithium Metal Batteries Enabled by Hierarchical Multifunctional Polymer Electrolytes with Near‐Single Ion Conduction', Angewandte Chemie, vol. 131, no. 18, pp. 6062-6067.View/Download from: Publisher's site
Zhou, D, Tkacheva, A, Tang, X, Sun, B, Shanmukaraj, D, Li, P, Zhang, F, Armand, M & Wang, G 2019, 'Stable Conversion Chemistry-Based Lithium Metal Batteries Enabled by Hierarchical Multifunctional Polymer Electrolytes with Near-Single Ion Conduction.', Angewandte Chemie (International ed. in English), vol. 58, no. 18, pp. 6001-6006.View/Download from: Publisher's site
The low Coulombic efficiency and serious safety issues resulting from uncontrollable dendrite growth have severely impeded the practical applications of lithium (Li) metal anodes. Herein we report a stable quasi-solid-state Li metal battery by employing a hierarchical multifunctional polymer electrolyte (HMPE). This hybrid electrolyte was fabricated via in situ copolymerizing lithium 1-[3-(methacryloyloxy)propylsulfonyl]-1-(trifluoromethanesulfonyl)imide (LiMTFSI) and pentaerythritol tetraacrylate (PETEA) monomers in traditional liquid electrolyte, which is absorbed in a poly(3,3-dimethylacrylic acid lithium) (PDAALi)-coated glass fiber membrane. The well-designed HMPE simultaneously exhibits high ionic conductivity (2.24×10-3 S cm-1 at 25 °C), near-single ion conducting behavior (Li ion transference number of 0.75), good mechanical strength and remarkable suppression for Li dendrite growth. More intriguingly, the cation permselective HMPE efficiently prevents the migration of negatively charged iodine (I) species, which provides the as-developed Li-I batteries with high capacity and long cycling stability.
Sun, B, Li, P, Zhang, J, Wang, D, Munroe, P, Wang, C, Notten, PHL & Wang, G 2018, 'Dendrite-Free Sodium-Metal Anodes for High-Energy Sodium-Metal Batteries.', Advanced materials (Deerfield Beach, Fla.), vol. 30, no. 29, pp. e1801334-e1801334.View/Download from: Publisher's site
Sodium (Na) metal is one of the most promising electrode materials for next-generation low-cost rechargeable batteries. However, the challenges caused by dendrite growth on Na metal anodes restrict practical applications of rechargeable Na metal batteries. Herein, a nitrogen and sulfur co-doped carbon nanotube (NSCNT) paper is used as the interlayer to control Na nucleation behavior and suppress the Na dendrite growth. The N- and S-containing functional groups on the carbon nanotubes induce the NSCNTs to be highly "sodiophilic," which can guide the initial Na nucleation and direct Na to distribute uniformly on the NSCNT paper. As a result, the Na-metal-based anode (Na/NSCNT anode) exhibits a dendrite-free morphology during repeated Na plating and striping and excellent cycling stability. As a proof of concept, it is also demonstrated that the electrochemical performance of sodium-oxygen (Na-O2 ) batteries using the Na/NSCNT anodes show significantly improved cycling performances compared with Na-O2 batteries with bare Na metal anodes. This work opens a new avenue for the development of next-generation high-energy-density sodium-metal batteries.
Sun, B, Pompe, C, Dongmo, S, Zhang, J, Kretschmer, K, Schröder, D, Janek, J & Wang, G 2018, 'Challenges for Developing Rechargeable Room-Temperature Sodium Oxygen Batteries', Advanced Materials Technologies, vol. 3, no. 9.View/Download from: Publisher's site
© 2018 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim The development of high energy-density and low-cost energy storage devices requires new chemistry beyond the horizon of current state-of-the-art lithium-ion batteries. Recently, sodium/oxygen (Na/O2) batteries have attracted great attention as one possible battery type among the new generation of rechargeable batteries. They convince with superior energy density, a relatively simple cell reaction, and abundance of sodium. Research on Na/O2batteries has progressed quickly in recent years. However, a fundamental understanding underpinning the complex chemical/electrochemical side reactions is still insufficient, and many challenges remain unsolved for real practical applications. Herein, recent achievements and remaining issues for the development of rechargeable Na/O2batteries are summarized. The discussion focuses on cell reaction mechanisms as well as cathode materials, sodium anodes, and electrolytes as key components of this type of battery. Furthermore, perspectives for future research and technological advances of Na/O2batteries are outlined.
Xie, X, Kretschmer, K, Anasori, B, Sun, B, Wang, G & Gogotsi, Y 2018, 'Porous Ti3C2Tx MXene for Ultrahigh-Rate Sodium-Ion Storage with Long Cycle Life', ACS APPLIED NANO MATERIALS, vol. 1, no. 2, pp. 505-511.View/Download from: Publisher's site
Xiong, P, Zhang, X, Zhang, F, Yi, D, Zhang, J, Sun, B, Tian, H, Shanmukaraj, D, Rojo, T, Armand, M, Ma, R, Sasaki, T & Wang, G 2018, 'Two-Dimensional Unilamellar Cation-Deficient Metal Oxide Nanosheet Superlattices for High-Rate Sodium Ion Energy Storage.', ACS Nano, vol. 12, pp. 12337-12346.View/Download from: Publisher's site
Cation-deficient two-dimensional (2D) materials, especially atomically thin nanosheets, are highly promising electrode materials for electrochemical energy storage that undergo metal ion insertion reactions, yet they have rarely been achieved thus far. Here, we report a Ti-deficient 2D unilamellar lepidocrocite-type titanium oxide (Ti0.87O2) nanosheet superlattice for sodium storage. The superlattice composed of alternately restacked defective Ti0.87O2 and nitrogen-doped graphene monolayers exhibits an outstanding capacity of ∼490 mA h g-1 at 0.1 A g-1, an ultralong cycle life of more than 10000 cycles with ∼0.00058% capacity decay per cycle, and especially superior low-temperature performance (100 mA h g-1 at 12.8 A g-1 and -5 °C), presenting the best reported performance to date. A reversible Na+ ion intercalation mechanism without phase and structural change is verified by first-principles calculations and kinetics analysis. These results herald a promising strategy to utilize defective 2D materials for advanced energy storage applications.
Yan, K, Sun, B, Munroe, P & Wang, G 2018, 'Three-dimensional pie-like current collectors for dendrite-free lithium metal anodes', ENERGY STORAGE MATERIALS, vol. 11, pp. 127-133.View/Download from: Publisher's site
Yang, W, Yang, W, Sun, B, Di, S, Yan, K, Wang, G & Shao, G 2018, 'Mixed Lithium Oxynitride/Oxysulfide as an Interphase Protective Layer To Stabilize Lithium Anodes for High-Performance Lithium-Sulfur Batteries.', ACS applied materials & interfaces, vol. 10, no. 46, pp. 39695-39704.View/Download from: Publisher's site
Lithium metal is strongly recognized as a promising anode material for next-generation high-energy-density systems. However, unstable solid electrolyte interphase and uncontrolled lithium dendrites growth induce severe capacity decay and short cycle life accompanied by high security risks. Here, we propose a simple method for constructing an artificial solid electrolyte interphase layer on the surface of lithium metal through spontaneous reaction, where ammonium persulfate and lithium nitrate are exploited as oxidants. The satisfactory artificial protective layer with uniform and dense morphology is composed of mixed lithium compounds, mainly including Li xSO y and Li xNO y species, which could effectively stabilize the interphase between electrolyte and lithium metal anode and restrain the "shuttle effect" of polysulfides. By employing the premodified lithium metal as anodes for lithium-sulfur batteries, the resulting cells exhibit excellent cycle stability (capacity decay of 0.09% per cycle over 300 cycles at 1 C and Coulombic efficiency of over 98%) and outstanding rate capability (850.8 mAh g-1 even at 4 C). Hence, introducing a stable artificial protective layer to protect lithium anode delivers a new strategy for solving the issues related to lithium-metal batteries.
Zhao, S, Sun, B, Yan, K, Zhang, J, Wang, C & Wang, G 2018, 'Aegis of Lithium-Rich Cathode Materials via Heterostructured LiAIF(4) Coating for High-Performance Lithium-Ion Batteries', ACS APPLIED MATERIALS & INTERFACES, vol. 10, no. 39, pp. 33260-33268.View/Download from: Publisher's site
Guo, X, Sun, B, Su, D, Liu, X, Liu, H, Wang, Y & Wang, G 2017, 'Recent developments of aprotic lithium-oxygen batteries: functional materials determine the electrochemical performance', Science Bulletin, vol. 62, no. 6, pp. 442-452.View/Download from: Publisher's site
© 2017 Lithium oxygen battery has the highest theoretical capacity among the rechargeable batteries and it can reform energy storage technology if it comes to commercialization. However, many critical challenges, mainly embody as low charge/discharge round-trip efficiency and poor cycling stability, impede the development of Li-O 2 batteries. The electrolyte decomposition, lithium metal anode corrosion and sluggish oxygen reaction kinetics at cathode are all responsible for poor electrochemical performances. Particularly, the catalytic cathode of Li-O 2 batteries, playing a crucial role to reduce the oxygen during discharging and to decompose discharge products during charging, is regarded as a breakthrough point that has been comprehensive investigated. In this review, the progress and issues of electrolyte, anode and cathode, especially the catalysts used at cathode, are systematically summarized and discussed. Then the perspectives toward the developments of a long life Li-O 2 battery are also presented at last.
Kretschmer, K, Sun, B, Zhang, J, Xie, X, Liu, H & Wang, G 2017, '3D Interconnected Carbon Fiber Network-Enabled Ultralong Life Na3 V2 (PO4 )3 @Carbon Paper Cathode for Sodium-Ion Batteries.', Small, vol. 13, no. 9.View/Download from: Publisher's site
Sodium-ion batteries (NIBs) are an emerging technology, which can meet increasing demands for large-scale energy storage. One of the most promising cathode material candidates for sodium-ion batteries is Na3 V2 (PO4 )3 due to its high capacity, thermal stability, and sodium (Na) Superionic Conductor 3D (NASICON)-type framework. In this work, the authors have significantly improved electrochemical performance and cycling stability of Na3 V2 (PO4 )3 by introducing a 3D interconnected conductive network in the form of carbon fiber derived from ordinary paper towel. The free-standing Na3 V2 (PO4 )3 -carbon paper (Na3 V2 (PO4 )3 @CP) hybrid electrodes do not require a metallic current collector, polymeric binder, or conducting additives to function as a cathode material in an NIB system. The Na3 V2 (PO4 )3 @CP cathode demonstrates extraordinary long term cycling stability for 30 000 deep charge-discharge cycles at a current density of 2.5 mA cm(-2) . Such outstanding cycling stability can meet the stringent requirements for renewable energy storage.
Mondal, AK, Kretschmer, K, Zhao, Y, Liu, H, Wang, C, Sun, B & Wang, G 2017, 'Nitrogen-Doped Porous Carbon Nanosheets from Eco-Friendly Eucalyptus Leaves as High Performance Electrode Materials for Supercapacitors and Lithium Ion Batteries.', Chemistry - A European Journal, vol. 23, no. 15, pp. 3683-3690.View/Download from: Publisher's site
Nitrogen-doped porous carbon nanosheets were prepared from eucalyptus tree leaves by simply mixing the leaf powders with KHCO3 and subsequent carbonisation. Porous carbon nanosheets with a high specific surface area of 2133 m(2) g(-1) were obtained and applied as electrode materials for supercapacitors and lithium ion batteries. For supercapacitor applications, the porous carbon nanosheet electrode exhibited a supercapacitance of 372 F g(-1) at a current density of 500 mA g(-1) in 1 m H2 SO4 aqueous electrolyte and excellent cycling stability over 15 000 cycles. In organic electrolyte, the nanosheet electrode showed a specific capacitance of 71 F g(-1) at a current density of 2 Ag(-1) and stable cycling performance. When applied as the anode material for lithium ion batteries, the as-prepared porous carbon nanosheets also demonstrated a high specific capacity of 819 mA h g(-1) at a current density of 100 mA g(-1) , good rate capability, and stable cycling performance. The outstanding electrochemical performances for both supercapacitors and lithium ion batteries are derived from the large specific surface area, porous nanosheet structure and nitrogen doping effects. The strategy developed in this paper provides a novel route to utilise biomass-derived materials for low-cost energy storage systems.
Sun, B, Kretschmer, K, Xie, X, Munroe, P, Peng, Z & Wang, G 2017, 'Hierarchical Porous Carbon Spheres for High-Performance Na-O2 Batteries.', Advanced Materials, vol. 29, no. 48, pp. 1-8.View/Download from: Publisher's site
As a new family member of room-temperature aprotic metal-O2 batteries, Na-O2 batteries, are attracting growing attention because of their relatively high theoretical specific energy and particularly their uncompromised round-trip efficiency. Here, a hierarchical porous carbon sphere (PCS) electrode that has outstanding properties to realize Na-O2 batteries with excellent electrochemical performances is reported. The controlled porosity of the PCS electrode, with macropores formed between PCSs and nanopores inside each PCS, enables effective formation/decomposition of NaO2 by facilitating the electrolyte impregnation and oxygen diffusion to the inner part of the oxygen electrode. In addition, the discharge product of NaO2 is deposited on the surface of individual PCSs with an unusual conformal film-like morphology, which can be more easily decomposed than the commonly observed microsized NaO2 cubes in Na-O2 batteries. A combination of coulometry, X-ray diffraction, and in situ differential electrochemical mass spectrometry provides compelling evidence that the operation of the PCS-based Na-O2 battery is underpinned by the formation and decomposition of NaO2 . This work demonstrates that employing nanostructured carbon materials to control the porosity, pore-size distribution of the oxygen electrodes, and the morphology of the discharged NaO2 is a promising strategy to develop high-performance Na-O2 batteries.
Zhang, J, Sun, B, McDonagh, AM, Zhao, Y, Kretschmer, K, Guo, X & Wang, G 2017, 'A multi-functional gel co-polymer bridging liquid electrolyte and solid cathode nanoparticles: An efficient route to Li–O2batteries with improved performance', Energy Storage Materials, vol. 7, pp. 1-7.View/Download from: Publisher's site
© 2016 Lithium-oxygen (Li–O 2 ) batteries have the highest theoretical energy density amongst all rechargeable batteries and have attracted significant attention. However, large over-potentials originating from sluggish reaction kinetics often lead to low round-trip energy efficiency and short cycle life. We report here a novel multi-functional gel co-polymer that efficiently enhances the discharge and charge performances in Li–O 2 batteries by intimately connecting the liquid electrolyte and solid cathode nanoparti cles. On one hand, the co-polymer material, poly(2,2,6,6-tetramethylpiperidinyloxy-4-yl methacrylate-co-methyl methacrylate) (P(TMA-MMA)), functions as a binder during the fabrication of the cathode and forms a gel polymer membrane to retain liquid electrolyte and to increase ionic conductivity. On the other hand, the TMA units, containing N–O radical groups that catalyse Li 2 O 2 formation and decomposition during charge and discharge cycles, are distributed throughout the polymer membrane. This allows more effective formation and decomposition of Li 2 O 2 than surface bound catalytic units. The combination of gelable MMA and catalytic TMA moieties enhances the interface between liquid electrolyte and solid cathode by functioning as a medium both to transport Li + (enhancing discharge process) and to carry electrons (reducing charge over-potential). Consequently, the optimized P(TMA-MMA) co-polymers provide exceptional electrochemical performance in Li–O 2 batteries.
Zhang, J, Sun, B, Zhao, Y, Kretschmer, K & Wang, G 2017, 'Modified Tetrathiafulvalene as an Organic Conductor for Improving Performances of Li−O 2 Batteries', Angewandte Chemie, vol. 129, no. 29, pp. 8625-8629.View/Download from: Publisher's site
Large over‐potentials owing to the sluggish kinetics of battery reactions have always been the drawbacks of Li−O2 batteries, which lead to short cycle life. Although redox mediators have been intensively investigated to overcome this issue, side‐reactions are generally induced by the solvated nature of redox mediators. Herein, we report an alternative method to achieve more efficient utilization of tetrathiafulvalene (TTF) in Li−O2 batteries. By coordinating TTF+ with LiCl during charging, an organic conductor TTF+Clx− precipitate covers Li2O2 to provide an additional electron‐transfer pathway on the surface, which can significantly reduce the charge over‐potential, improve the energy efficiency of Li−O2 batteries, and eliminate side‐reactions between the lithium metal anode and TTF+. When a porous graphene electrode is used, the Li−O2 battery combined with TTF and LiCl shows an outstanding performance and prolonged cycle life.
Zhang, J, Sun, B, Zhao, Y, Kretschmer, K & Wang, G 2017, 'Modified Tetrathiafulvalene as an Organic Conductor for Improving Performances of Li-O2 Batteries.', Angewandte Chemie, vol. 56, no. 29, pp. 8505-8509.View/Download from: Publisher's site
Large over-potentials owing to the sluggish kinetics of battery reactions have always been the drawbacks of Li-O2 batteries, which lead to short cycle life. Although redox mediators have been intensively investigated to overcome this issue, side-reactions are generally induced by the solvated nature of redox mediators. Herein, we report an alternative method to achieve more efficient utilization of tetrathiafulvalene (TTF) in Li-O2 batteries. By coordinating TTF+ with LiCl during charging, an organic conductor TTF+ Clx- precipitate covers Li2 O2 to provide an additional electron-transfer pathway on the surface, which can significantly reduce the charge over-potential, improve the energy efficiency of Li-O2 batteries, and eliminate side-reactions between the lithium metal anode and TTF+ . When a porous graphene electrode is used, the Li-O2 battery combined with TTF and LiCl shows an outstanding performance and prolonged cycle life.
Guo, X, Sun, B, Zhang, J, Liu, H & Wang, G 2016, 'Ruthenium decorated hierarchically ordered macro-mesoporous carbon for lithium oxygen batteries', JOURNAL OF MATERIALS CHEMISTRY A, vol. 4, no. 25, pp. 9774-9780.View/Download from: Publisher's site
Song, J, Sun, B, Liu, H, Ma, Z, Chen, Z, Shao, G & Wang, G 2016, 'Enhancement of the Rate Capability of LiFePO4 by a New Highly Graphitic Carbon-Coating Method', ACS Applied Materials and Interfaces, vol. 8, no. 24, pp. 15225-15231.View/Download from: Publisher's site
Low lithium ion diffusivity and poor electronic conductivity are two major drawbacks for the wide application of LiFePO4 in high-power lithium ion batteries. In this work, we report a facile and efficient carbon-coating method to prepare LiFePO4/graphitic carbon composites by in situ carbonization of perylene-3,4,9,10-tetracarboxylic dianhydride during calcination. Perylene-3,4,9,10-tetracarboxylic dianhydride containing naphthalene rings can be easily converted to highly graphitic carbon during thermal treatment. The ultrathin layer of highly graphitic carbon coating drastically increased the electronic conductivity of LiFePO4. The short pathway along the  direction of LiFePO4 nanoplates could decrease the Li+ ion diffusion path. In favor of the high electronic conductivity and short lithium ion diffusion distance, the LiFePO4/graphitic carbon composites exhibit an excellent cycling stability at high current rates at room temperature and superior performance at low temperature (−20 °C).
Chen, S, Ao, Z, Sun, B, Xie, X & Wang, G 2016, 'Porous carbon nanocages encapsulated with tin nanoparticles for high performance sodium-ion batteries', Energy Storage Materials, vol. 5, pp. 180-190.View/Download from: Publisher's site
© 2016 Sodium-ion batteries (SIBs) are recognized as an alternative to lithium ion batteries due to the abundance o f sodium and potentially low cost of the whole battery system. One of the major challenges facing SIBs is to develop suitable anode materials with high capacity and long cycling life. Herein, we report the synthesis of porous carbon nanocage-Sn (PCNCs-Sn) nanocomposites as anodes of SIBs, demonstrating a high capacity of 828 mAh g −1 at 40 mA g −1 . The electrodes also exhibited good rate capabilities (up to 3C) and superior cycling performances (1000 cycles). Post-mortem analyses verified the efficient volume change restriction by carbon nanocages and the well-preserved porous structure. Theoretical calculations indicated that the pulverization of bare Sn electrodes could be ascribed to strong bonds formed between amorphous carbon and the discharge product (Na 15 Sn 4 ), which also deteriorated the conductivity. In contrast, the relatively weak interaction between Na 15 Sn 4 and graphitic carbon can maintain superior conductivity and structural stability for better cycling performance.
Kretschmer, K, Sun, B, Xie, X, Chen, S & Wang, G 2016, 'A free-standing LiFePO4-carbon paper hybrid cathode for flexible Lithium-ion batteries', Green Chemistry, vol. 18, no. 9, pp. 2691-2698.View/Download from: Publisher's site
Lithium-ion batteries (LIBs) are widely implemented to power portable electronic devices and are increasingly
in demand for large-scale applications. One of the major obstacles for this technology is still the low
cost-efficiency of its electrochemical active materials and production processes. In this work, we present
a novel impregnation–carbothermal reduction method to generate a LiFePO4–carbon paper hybrid
electrode, which doesn't require a metallic current collector, polymeric binder or conducting additives to
function as a cathode material in a LIB system. A shell of LiFePO4 crystals was grown in situ on carbon
fibres during the carbonization of microcrystalline cellulose. The LiFePO4–carbon paper electrode
achieved an initial reversible areal capacity of 197 µA h cm−2 increasing to 222 µA h cm−2 after 500 cycles
at a current density of 0.1 mA cm−2
. The hybrid electrode also demonstrated a superior cycling performance
for up to 1000 cycles. The free-standing electrode could be potentially applied for flexible
Sun, B, Guo, L, Ju, Y, Munroe, P, Wang, E, Peng, Z & Wang, G 2016, 'Unraveling the catalytic activities of ruthenium nanocrystals in highperformance aprotic Li–O₂ batteries', Nano Energy, vol. 28, pp. 486-494.View/Download from: Publisher's site
Ruthenium (Ru)-catalyzed aprotic Li–O2 batteries have attracted a great deal of interests because of their excellent electrochemical performances including high specific energy and round-trip efficiency. However, it remains unclear how the incorporated Ru catalysts function to enhance the batteries' performance. Herein, we report Ru nanocrystal-catalyzed carbon nanotube-based aprotic Li–O2 batteries with electrochemical performances that can match or even surpass some of the best literature results. The catalytic mechanism of Ru nanocrystals has been studied by a combination of Coulometry and in situ differential electrochemical mass spectrometry (DEMS). It has been found that through the synergy of water additive in electrolyte and Ru-based catalysts, the charging reaction overpotential can be brought down to 0.12 V (usually η>1 V). Moreover, an isotope-labeled DEMS study on the electrochemical oxidation of Li213CO3 indicated that Ru nanocrystals also have the capability to decompose Li2CO3, a detrimental by-product formed in almost all aprotic Li–O2 batteries, at a surprisingly low potential of ~3.5 V vs. Li/Li+ (usually >4.0 V). The capabilities of Ru nanocrystals to decompose Li2O2, LiOH, and Li2CO3 at low voltages, which drastically decreases the degradation of electrode and/or electrolyte, are crucial to achieve outstanding electrochemical performances for Li–O2 batteries.
Wei, Y, Sun, B, Su, D, Zhu, J & Wang, G 2016, '3D Free-Standing NiCo2O4@graphene Foam for High-Performance Supercapacitors', ENERGY TECHNOLOGY, vol. 4, no. 6, pp. 737-743.View/Download from: Publisher's site
Zhang, J, Sun, B, Xie, X, Zhao, Y & Wang, G 2016, 'A Bifunctional Organic Redox Catalyst for Rechargeable Lithium-Oxygen Batteries with Enhanced Performances', ADVANCED SCIENCE, vol. 3, no. 4.View/Download from: Publisher's site
Sun, B, Chen, S, Liu, H & Wang, G 2015, 'Mesoporous Carbon Nanocube Architecture for High-Performance Lithium-Oxygen Batteries', ADVANCED FUNCTIONAL MATERIALS, vol. 25, no. 28, pp. 4436-4444.View/Download from: Publisher's site
Zhao, Y, Chen, S, Sun, B, Su, D, Huang, X, Liu, H, Yan, Y, Sun, K & Wang, G 2015, 'Graphene-Co3O4 nanocomposite as electrocatalyst with high performance for oxygen evolution reaction', SCIENTIFIC REPORTS, vol. 5.View/Download from: Publisher's site
Zhao, Y, Sun, B, Huang, X, Liu, H, Su, D, Sun, K & Wang, G 2015, 'Porous graphene wrapped CoO nanoparticles for highly efficient oxygen evolution', JOURNAL OF MATERIALS CHEMISTRY A, vol. 3, no. 10, pp. 5402-5408.View/Download from: Publisher's site
Chen, S, Sun, B, Xie, X, Mondal, AK, Huang, X & Wang, G 2015, 'Multi-chambered micro/mesoporous carbon nanocubes as new polysulfides reserviors for lithium-sulfur batteries with long cycle life', NANO ENERGY, vol. 16, pp. 268-280.View/Download from: Publisher's site
Chen, S, Zhao, Y, Sun, B, Ao, Z, Xie, X, Wei, Y & Wang, G 2015, 'Microwave-assisted Synthesis of Mesoporous Co3O4 Nanoflakes for Applications in Lithium Ion Batteries and Oxygen Evolution Reactions', ACS APPLIED MATERIALS & INTERFACES, vol. 7, no. 5, pp. 3306-3313.View/Download from: Publisher's site
Kretschmer, K, Sun, B, Su, D, Zhao, Y & Wang, G 2015, 'Scalable Preparation of LiFePO4/C Nanocomposites with sp(2)-Coordinated Carbon Coating as High-Performance Cathode Materials for Lithium-Ion Batteries', CHEMELECTROCHEM, vol. 2, no. 12, pp. 2096-2103.View/Download from: Publisher's site
Xie, X, Chen, S, Sun, B, Wang, C & Wang, G 2015, '3D Networked Tin Oxide/Graphene Aerogel with a Hierarchically Porous Architecture for High-Rate Performance Sodium-Ion Batteries', CHEMSUSCHEM, vol. 8, no. 17, pp. 2948-2955.View/Download from: Publisher's site
Xie, X, Kretschmer, K, Zhang, J, Sun, B, Su, D & Wang, G 2015, 'Sn@CNT nanopillars grown perpendicularly on carbon paper: A novel free-standing anode for sodium ion batteries', NANO ENERGY, vol. 13, pp. 208-217.View/Download from: Publisher's site
Zhang, J, Sun, B, Xie, X, Kretschmer, K & Wang, G 2015, 'Enhancement of stability for lithium oxygen batteries by employing electrolytes gelled by poly(vinylidene fluoride-co-hexafluoropropylene) and tetraethylene glycol dimethyl ether', Electrochimica Acta, vol. 183, pp. 56-62.View/Download from: Publisher's site
© 2015 Elsevier Ltd. Free-standing gel polymer electrolytes with poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) matrix plasticized with tetraethylene glycol dimethyl ether (TEGDME) were prepared and investigated. The as-prepared gel polymer electrolytes exhibited large operating window and acceptable ionic conductivity. When applied in lithium oxygen batteries, the gel polymer electrolyte could support a high initial discharge capacity of 2988mAhg-1 when a carbon black electrode without catalyst was used as cathode. Furthermore, the battery with gel polymer electrolyte can last at least 50 cycles in the fixed capacity cycling, displaying an excellent stability. Detailed study reveals that the gelling process is essential for the cycling stability enhancement. With excellent electrochemical properties, the free-standing gel polymer electrolyte presented in this investigation has great application potentials in long-life lithium oxygen batteries.
Chen, S, Huang, X, Liu, H, Sun, B, Yeoh, W, Li, K, Zhang, J & Wang, G 2014, '3D Hyperbranched Hollow Carbon Nanorod Architectures for High-Performance Lithium-Sulfur Batteries', Advanced Energy Materials, vol. 4, p. 1301761.View/Download from: Publisher's site
Lithium-sulfur batteries have been plagued for a long time by low Coulombic efficiency, fast capacity loss, and poor high rate performance. Here, the synthesis of 3D hyperbranched hollow carbon nanorod encapsulated sulfur nanocomposites as cathode materials for lithium-sulfur batteries is reported. The sulfur nanocomposite cathodes deliver a high specific capacity of 1378 mAh g-1 at a 0.1C current rate and exhibit stable cycling performance. The as-prepared sulfur nanocomposites also achieve excellent high rate capacities and cyclability, such as 990 mAh g -1 at 1C, 861 mAh g -1 at 5C, and 663 mAh g -1 at 10C, extending to more than 500 cycles. The superior electrochemical performance are ascribed to the unique 3D hyperbranched hollow carbon nanorod architectures and high length/radius aspect ratio of the carbon nanorods, which can effectively prevent the dissolution of polysulfi des, decrease self-discharge, and confi ne the volume expansion on cycling. High capacity, excellent high-rate performance, and long cycle life render the as-developed sulfur/carbon nanorod nanocomposites a promising cathode material for lithium-sulfur batteries.
Chen, S, Huang, X, Sun, B, Zhang, J, Liu, H & Wang, G 2014, 'Multi-shelled hollow carbon nanospheres for lithium–sulfur batteries with superior performances', J. Mater. Chem. A, vol. 2, no. 38, pp. 16199-16207.View/Download from: Publisher's site
Chen, S, Bao, P, Huang, X, Sun, B & Wang, G 2014, 'Hierarchical 3D mesoporous silicon@graphene nanoarchitectures for lithium ion batteries with superior performance', Nano Research, vol. 7, no. 1, pp. 85-94.View/Download from: Publisher's site
Silicon has been recognized as the most promising anode material for high capacity lithium ion batteries. However, large volume variations during charge and discharge result in pulverization of Si electrodes and fast capacity loss on cycling. This drawback of Si electrodes can be overcome by combination with well-organized graphene foam. In this work, hierarchical three-dimensional carbon-coated mesoporous Si nanospheres@graphene foam (C@Si@GF) nanoarchitectures were successfully synthesized by a thermal bubble ejection assisted chemical-vapor-deposition and magnesiothermic reduction method. The morphology and structure of the as-prepared nanocomposites were characterized by field emission scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. When employed as anode materials in lithium ion batteries, C@Si@GF nanocomposites exhibited superior electrochemical performance including a high specific capacity of 1,200 mAh/g at the current density of 1 A/g, excellent high rate capabilities and an outstanding cyclability. Post-mortem analyses identified that the morphology of 3D C@Si@GF electrodes after 200 cycles was well maintained. The synergistic effects arising from the combination of mesoporous Si nanospheres and graphene foam nanoarchitectures may address the intractable pulverization problem of Si electrode.
Huang, X, Sun, B, Chen, S & Wang, G 2014, 'Self-Assembling Synthesis of Free-standing Nanoporous Graphene-Transition-Metal Oxide Flexible Electrodes for High-Performance Lithium-Ion Batteries and Supercapacitors', Chemistry An Asian Journal, vol. 9, no. 1, pp. 206-211.View/Download from: Publisher's site
The synthesis of nanoporous graphene by a convenient carbon nanofiber assisted self-assembly approach is reported. Porous structures with large pore volumes, high surface areas, and well-controlled pore sizes were achieved by employing spherical silica as hard templates with different diameters. Through a general wet-immersion method, transition-metal oxide (Fe3O4, Co3O4, NiO) nanocrystals can be easily loaded into nanoporous graphene papers to form three-dimensional flexible nanoarchitectures. When directly applied as electrodes in lithium-ion batteries and supercapacitors, the materials exhibited superior electrochemical performances, including an ultra-high specific capacity, an extended long cycle life, and a high rate capability. In particular, nanoporous Fe3O4-graphene composites can deliver a reversible specific capacity of 1427.5 mAh-g-1 at a high current density of 1000 mA-g-1 as anode materials in lithium-ion batteries. Furthermore, nanoporous Co3O4 graphene composites achieved a high supercapacitance of 424.2 F-g-1. This work demonstrated that the as-developed freestanding nanoporous graphene papers could have significant potential for energy storage and conversion applications.
Huang, X, Sun, B, Su, D, Zhao, D & Wang, G 2014, 'Soft-template synthesis of 3D porous graphene foams with tunable architectures for lithium-O2 batteries and oil adsorption applications', Journal of Materials Chemistry A, vol. 2, pp. 7973-7979.View/Download from: Publisher's site
We report a general emulsion soft-template method to synthesize porous graphene foams for multifunctional applications, including lithiumoxygen batteries and oil-adsorption. Multiple micro-emulsions and micelles were employed to produce three-dimensional porous graphene with well-tailored interarchitecture for the first time. Detailed mechanism study reveals that specific interfacial interactions, such as pp interaction, hydrophobic affinity or electrostatic interaction, are vital for the formation of porous graphene materials. When applied as cathode materials in lithiumoxygen batteries, the porous graphene foams exhibited good catalytic activity. Besides, the porous graphene materials also demonstrated the capability for oil adsorption with a high efficiency.
Liu, Q, Yang, Y, Sun, B, Su, D, li, Z, Xia, Q & Wang, G 2014, 'Hydrothermal synthesis of FeP4 and Fe2P-loaded alpha-Fe2O3 hollow spheres and applications in gas sensors', Sensors and Actuators B: Chemical, vol. 194, pp. 27-32.View/Download from: Publisher's site
FeP4 and Fe2P-loaded hematite (alpha-Fe2O3) (FFH) hollow spheres with a diameter of 130410 nm were synthesized by a hydrothermal method. The structure and morphology of the FFH hollow spheres were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), field-emission scanning electron microscope (FESEM), and X-ray photoelectron spectroscopy (XPS). Nitrogen adsorptiondesorption isothermal measurements revealed that the FFH hollow spheres have larger BET surface area and mesopores. The gas-sensing performance of the FFH hollow spheres was investigated towards a series of typical organic solvents and fuels. The FFH hollow spheres exhibited a superior sensitivity towards flammable and irritant gases. The possible sensing mechanism of the FFH hollow spheres sensor is also proposed.
Mondal, AK, Su, D, Chen, S, Sun, B, Li, K & Wang, G 2014, 'A simple approach to prepare nickel hydroxide nanosheets for enhanced pseudocapacitive performance', RSC Advances, vol. 4, pp. 19476-19481.View/Download from: Publisher's site
Nickel hydroxide nanosheets were synthesized by a simple microwave assisted heating method and investigated as electrochemical pseudo-capacitive materials for supercapacitors. The crystalline structure and morphology of the as-obtained Ni(OH)2 nanosheets were characterized by X-ray di?raction, nitrogen adsorptiondesorption isotherms, ?eld emission scanning electron microscopy and transmission electron microscopy. The electrochemical properties of the Ni(OH)2 nanosheets were evaluated by cyclic voltammetry and chronopotentiometry technology in 2 M KOH solution. The nickel hydroxide nanosheet electrode shows a maximum speci?c capacitance of 2570 F g-1 at a current density of 5 A g-1 and exhibits superior cycling stability. These results suggest its potential application as an electrode material for supercapacitors.
Sun, B, Huang, X, Chen, S, Munroe, P & Wang, G 2014, 'Porous Graphene Nanoarchitectures: An Efficient Catalyst for Low Charge-Overpotential, Long Life, and High Capacity Lithium-Oxygen Batteries', Nano Letters, vol. 14, pp. 3145-3152.View/Download from: Publisher's site
The electrochemical performance of lithium-oxygen (Li-O2) batteries awaits dramatic improvement in the design of porous cathode electrodes with sufficient spaces to accommodate the discharge products and discovery of effective cathode catalysts to promote both oxygen reduction reactions and oxygen evolution reactions. Herein, we report the synthesis of porous graphene with different pore size architectures as cathode catalysts for Li-O2 batteries. Porous graphene materials exhibited significantly higher discharge capacities than that of nonporous graphene. Furthermore, porous graphene with pore diameter around 250 nm showed the highest discharge capacity among the porous graphene with the small pores (about 60 nm) and large pores (about 400 nm). Moreover, we discovered that addition of ruthenium (Ru) nanocrystals to porous graphene promotes the oxygen evolution reaction. The Ru nanocrystal-decorated porous graphene exhibited an excellent catalytic activity as cathodes in Li-O2 batteries with a high reversible capacity of 17 700 mA h g-1, a low charge/discharge overpotential (about 0.355 V), and a long cycle life up to 200 cycles (under the curtaining capacity of 1000 mAh g-1). The novel porous graphene architecture inspires the development of high-performance Li-O2 batteries.
Sun, B, Huang, X, Chen, S, Zhang, J & Wang, G 2014, 'An optimized LiNO3/DMSO electrolyte for high-performance rechargeable LiO2 batteries', RSC Advances, vol. 4, pp. 11115-11120.View/Download from: Publisher's site
Finding stable electrolytes is essential to address the poor cycling capability of current rechargeable non-aqueous LiO2 batteries. An optimized dimethyl sulfoxide (DMSO) based electrolyte using lithium nitrate (LiNO3) as the lithium salt has been first investigated for rechargeable LiO2 batteries. The charge over-potential of LiO2 batteries with LiNO3/DMSO electrolyte is 0.42 V lower than that of batteries with LiClO4/DMSO electrolyte. The LiO2 batteries with LiNO3/DMSO electrolyte also showed excellent high C-rate performance and good cycling stability.
Sun, B, Huang, X, Chen, S, Zhao, Y, Zhang, J, Munroe, P & Wang, G 2014, 'Hierarchical macroporous/mesoporous NiCo2O4 nanosheets as cathode catalysts for rechargeable Li-O2 batteries', Journal of Materials Chemistry A, vol. 2, pp. 12053-12059.View/Download from: Publisher's site
The key factor to improve the electrochemical performance of Li-O2 batteries is to find bi-functional cathode catalysts to promote the oxygen reduction and evolution reactions. Despite tremendous effects, developing cathode catalysts with high activity remains a great challenge. Herein, we report the synthesis of hierarchical macroporous/mesoporous NiCo2O4 nanosheets as an effective cathode catalyst for Li-O2 batteries. The hierarchical porous catalyst was synthesized by a hydrothermal method, followed by low temperature calcination. SEM and TEM observations clearly present that the as-prepared NiCo2O4 nanosheets showed a hierarchical porous structure with mesopores distributed through the surface of NiCo2O4 nanosheets and macropores formed between the crumpled nanosheets. When investigating as the cathode catalyst in Li-O2 batteries, the as-prepared NiCo2O4 nanosheets exhibited higher reversible capacity, lower charge/discharge overpotential, and better cycling stability than those of pristine carbon black. The enhanced electrochemical performance of NiCo2O4 nanosheets should be attributed not only to the high catalytic activity of NiCo2O4 towards oxygen reduction reaction and oxygen evolution reaction, but also to the novel hierarchical porous structure of NiCo2O4.
Wang, B, Wen, Y, Ye, D, Yu, H, Sun, B, Wang, G, Hulicova-Jurcakova, D & Wang, L 2014, 'Dual Protection of Sulfur by Carbon Nanospheres and Graphene Sheets for LithiumSulfur Batteries', Chemistry -A European Journal, vol. 20, pp. 5224-5230.View/Download from: Publisher's site
Well-confined elemental sulfur was implanted into a stacked block of carbon nanospheres and graphene sheets through a simple solution process to create a new type of composite cathode material for lithiumsulfur batteries. Transmission electron microscopy and elemental mapping analysis confirm that the as-prepared composite material consists of graphene-wrapped carbon nanospheres with sulfur uniformly distributed in between, where the carbon nanospheres act as the sulfur carriers. With this structural design, the graphene contributes to direct coverage of sulfur to inhibit the mobility of polysulfides, whereas the carbon nanospheres undertake the role of carrying the sulfur into the carbon network. This composite achieves a high loading of sulfur (64.2 wt%) and gives a stable electrochemical performance with a maximum discharge capacity of 1394 mAhg1 at a current rate of 0.1 C as well as excellent rate capability at 1 C and 2 C. The improved electrochemical properties of this composite material are attributed to the dual functions of the carbon components, which effectively restrain the sulfur inside the carbon nano-network for use in lithiumsulfur rechargeable batteries.
Wei, Y, Chen, S, Su, D, Sun, B, Zhu, J & Wang, G 2014, '3D Mesoporous Hybrid NiCo2O4@graphene Nanoarchitectures as Electrode Materials for Supercapacitors with Enhanced Performances', Journal of Materials Chemistry A, vol. 2, pp. 8103-8109.View/Download from: Publisher's site
3D mesoporous hybrid NiCo2O4@graphene nanoarchitectures were successfully synthesized by a combination of freeze drying and hydrothermal reaction. Field-emission scanning electron microscopy (FESEM) and TEM analyses revealed that NiCo2O4@graphene nanostructures consist of a hierarchical mesoporous sheet-on-sheet nanoarchitecture with a high specific surface area of 194 m2 g-1. Ultrathin NiCo2O4 nanosheets, with a thickness of a few nanometers and mesopores ranging from 2 to 5 nm, were wrapped in graphene nanosheets and formed hybrid nanoarchitectures. When applied as electrode materials in supercapacitors, hybrid NiCo2O4@graphene nanosheets exhibited a high capacitance of 778 F g-1 at the current density of 1 A g-1, and an excellent cycling performance extending to 10000 cycles at the high current density of 10 A g-1.
Xie, X, Su, D, Sun, B, Zhang, J, Wang, C & Wang, G 2014, 'Synthesis of Single-Crystalline Spinel LiMn2O4 Nanorods for Lithium-Ion Batteries with High Rate Capability and Long Cycle Life', CHEMISTRY-A EUROPEAN JOURNAL, vol. 20, no. 51, pp. 17125-17131.View/Download from: Publisher's site
Zhang, J, Chen, S, Xie, X, Kretschmer, K, Huang, X, Sun, B & Wang, G 2014, 'Porous poly(vinylidene fluoride-co-hexafluoropropylene) polymer membrane with sandwich-like architecture for highly safe lithium ion batteries', JOURNAL OF MEMBRANE SCIENCE, vol. 472, pp. 133-140.View/Download from: Publisher's site
Zhang, J, Sun, B, Huang, X, Chen, S & Wang, G 2014, 'Honeycomb-like porous gel polymer electrolyte membrane for lithium ion batteries with enhanced safety', Scientific Reports, vol. 4, pp. 1-7.View/Download from: Publisher's site
Lithium ion batteries have shown great potential in applications as power sources for electric vehicles and
large-scale energy storage. However, the direct uses of flammable organic liquid electrolyte with commercial
separator induce serious safety problems including the risk of fire and explosion. Herein, we report the
development of poly(vinylidene difluoride-co-hexafluoropropylene) polymer membranes with multi-sized
honeycomb-like porous architectures. The as-prepared polymer electrolyte membranes contain porosity as
high as 78%, which leads to the high electrolyte uptake of 86.2 wt%. The PVDF-HFP gel polymer electrolyte
membranes exhibited a high ionic conductivity of 1.03 mS cm21 at room temperature, which is much higher
than that of commercial polymer membranes. Moreover, the as-obtained gel polymer membranes are also
thermally stable up to 3506C and non-combustible in fire (fire-proof). When applied in lithium ion batteries
with LiFePO4 as cathode materials, the gel polymer electrolyte demonstrated excellent electrochemical
performances. This investigation indicates that PVDF-HFP gel polymer membranes could be potentially
applicable for high power lithium ion batteries with the features of high safety, low cost and good
Huang, X, Sun, B, Li, K, Chen, S & Wang, G 2013, 'Mesoporous graphene paper immobilised sulfur as a flexible electrode for lithium-sulfur batteries', Journal of Materials Chemistry A, vol. 1, no. 43, pp. 13484-13489.View/Download from: Publisher's site
Free-standing flexible mesoporous graphene-sulfur nanocomposite electrodes have been prepared by a sulfur vapor treatment approach. Amorphous sulfur homogeneously was distributed in the mesoporous architectures of porous graphene paper, in which sulfur was immobilized. The as-prepared mesoporous graphenesulfur papers can be directly applied as electrodes in lithiumsulfur batteries without using a binder, conductive additives or an extra current collector. The conductive flexible porous graphene networks can effectively facilitate electron transfer and electrolyte diffusion. The free-standing sulfurgraphene nanocomposite electrodes achieved a high discharge capacity of 1393 mA h g-1 with an enhanced cycling stability and good rate performance.
Sun, B, Munroe, P & Wang, G 2013, 'Ruthenium nanocrystals as cathode catalysts for lithium-oxygen batteries with a superior performance', SCIENTIFIC REPORTS, vol. 3.View/Download from: Publisher's site
Sun, B, Wang, Y, Wang, B, Kim, H, Kim, W & Wang, G 2013, 'Porous LiFePO4/C microspheres as high-power cathode materials for lithium ion batteries', Journal of Nanoscience and Nanotechnology, vol. 13, no. 5, pp. 3655-3659.View/Download from: Publisher's site
Porous LiFePO4/C microspheres were synthesized by a novel hydrothermal reaction combined with high-temperature calcinations. The morphology of the prepared material was investigated by fieldemission scanning electron microscopy. Porous microspheres with diameters around 1â3m were obtained, which consisting of primary LiFePO4 nanoparticles. The electrochemical performances of the as-prepared LiFePO4 microspheres were evaluated by cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic chargeâdischarge cycling. The carbon coated LiFePO4 microspheres showed lower polarization, higher rate capability, and better cycling stability than that of pristine LiFePO4 microspheres, indicating the potential application as the cathode material for high-power lithium ion batteries.
Sun, B, Zhang, J, Munroe, P, Ahn, H & Wang, G 2013, 'Hierarchical NiCo2O4 nanorods as an efficient cathode catalyst for rechargeable non-aqueous Li-O2 batteries', Electrochemistry Communications, vol. 31, pp. 88-91.View/Download from: Publisher's site
NiCo2O4 nanorods were synthesized by a hydrothermal method followed by low temperature calcination. FESEM and TEM analyses confirmed that the as-prepared materials consist of a hierarchical nanorod structure. When applied as cathode catalysts in rechargeable LiO2 batteries, NiCo2O4 nanorods exhibited a superior catalytic activity, including low charge over-potential, high discharge capacity and high-rate capability.
Wang, B, Wang, Y, Sun, B, Munroe, P & Wang, G 2013, 'Coral-like V2O5 nanowhiskers as high-capacity cathode materials for lithium-ion batteries', RSC Advances, vol. 3, pp. 5069-5075.View/Download from: Publisher's site
Coral-like V2O5 nanowhiskers were prepared by a direct electrolytic synthesis method. The as-prepared V2O5 nanowhiskers are approximately 1 Î¼m in length and 50â60 nm in width, which was confirmed by scanning electron microscopy and transmission electron microscopy analysis. When applied as cathode materials in lithium-ion batteries and combined with an ionic liquid electrolyte, the V2O5 nanowhiskers exhibited an initial capacity of 461 mAh gâ1, which is a significant enhancement compared to commercial V2O5 powders. The high rate performance of the V2O5 nanowhiskers was further improved at an elevated working temperature of 50 Â°C. The V2O5 nanowhiskers demonstrated a high specific capacity and an excellent high-rate performance at elevated temperatures.
Zhang, J, Sun, B, Ahn, H, Wang, C & Wang, G 2013, 'Conducting polymer-doped polyprrrole as an effective cathode catalyst for Li-O2 batteries', Materials Research Bulletin, vol. 48, no. 12, pp. 4979-4983.View/Download from: Publisher's site
Polypyrrole conducting polymers with different dopants have been synthesized and applied as the cathode catalyst in Li-O2 batteries. Polypyrrole polymers exhibited an effective catalytic activity towards oxygen reduction in lithium oxygen batteries. It was discovered that dopant significantly influenced the electrochemical performance of polypyrrole. The polypyrrole doped with Cl- demonstrated higher capacity and more stable cyclability than that doped with ClO4-. Polypyrrole conducting polymers also exhibited higher capacity and better cycling performance than that of carbon black catalysts.
Liu, H, Su, D, Zhou, R, Sun, B, Wang, G & Qiao, SZ 2012, 'Highly ordered mesoporous MoS2 with expanded spacing of the (002) crystal plane for ultrafast lithium ion storage', Advanced Energy Materials, vol. 2, no. 8, pp. 970-975.View/Download from: Publisher's site
Many alternative energy technologies have been developed in an attempt to alleviate the critical problems of an escalating energy crisis and greenhouse gas pollution, derived from the consumption of fossil fuels. Rechargeable lithium ion batteries have attracted great attention at fundamental application levels because of their high energy density and design fl exibility. As such, they are considered as the most promising next generation power sources for electric vehicles. The development of electric vehicles and hybrid electric vehicles demands high power energy sources which can operate under much higher current condition (tens of Amperes) than the operating current of mobilephones ( ~ 100 milli-Amperes).
Sun, B, Liu, H, Munroe, P, Ahn, H & Wang, G 2012, 'Nanocomposites of CoO and a mesoporous carbon (CMK-3) as a high performance cathode catalyst for lithium-oxygen batteries', Nano Research, vol. 5, no. 7, pp. 460-469.View/Download from: Publisher's site
A nanocomposite of CoO and a mesoporous carbon (CMK-3) has been studied as a cathode catalyst for lithium-oxygen batteries in alkyl carbonate electrolytes. The morphology and structure of the as-prepared nanocomposite were characterized by field emission scanning electron microscopy, transmission electron microscopy and high resolution transmission electron microscopy. The electrochemical properties of the mesoporous CoO/CMK-3 nanocomposite as a cathode catalyst in lithium-oxygen batteries were studied using galvanostatic charge-discharge methods. The reaction products on the cathode were analyzed by Fourier transform infrared spectroscopy. The CoO/CMK-3 nanocomposite exhibited better capacity retention than bare mesoporous CMK-3 carbon, Super-P carbon or CoO/Super-P nanocomposite. The synergistic effects arising from the combination of CoO nanoparticles and the mesoporous carbon nanoarchitecture may be responsible for the optimum catalytic performance in lithium-oxygen batteries.
Sun, B, Wang, B, Su, D, Xiao, LH, Ahn, H & Wang, G 2012, 'Graphene nanosheets as cathode catalysts for lithium-air batteries with an enhanced electrochemical performance', Carbon, vol. 50, no. 2, pp. 727-733.View/Download from: Publisher's site
Graphene nanosheets have been investigated as cathode catalysts for lithium-air batteries with alkyl carbonate electrolyte. Field emission scanning electron microscopy, transmission electron microscope and Raman spectroscopy have confirmed the high quality of the as-prepared graphene nanosheets and the surface analysis has identified the mesoporous characteristic of graphene nanosheets. The electrochemical properties of graphene nanosheets as cathode catalysts in lithium-air batteries were evaluated by a galvanostatic charge/discharge testing. The reaction products on the graphene nanosheets cathode were analyzed by X-ray diffraction and Fourier transform infrared spectroscopy. The graphene nanosheet electrodes exhibited a much better cycling stability and lower overpotential than that of the Vulcan XC-72 carbon. This work demonstrated that graphene nanosheets could be an efficient catalyst for lithium-air batteries.
Wang, Y, Park, J, Sun, B, Ahn, H & Wang, G 2012, 'Wintersweet-flower-like CoFe2O4/MWCNTs hybrid material for high-capacity reversible lithium storage', Chemistry - An Asian Journal, vol. 7, no. 8, pp. 1940-1946.View/Download from: Publisher's site
Abstract CoFe2O4/multiwalled carbon nanotubes (MWCNTs) hybrid materials were synthesized by a hydrothermal method. Field emission scanning electron microscopy and transmission electron microscopy analysis confirmed the morphology of the as-prepared hybrid material resembling wintersweet flower âbuds on branchesâ, in which CoFe2O4 nanoclusters, consisting of nanocrystals with a size of 5â10ânm, are anchored along carbon nanotubes. When applied as an anode material in lithium ion batteries, the CoFe2O4/MWCNTs hybrid material exhibited a high performance for reversible lithium storage. In particular, the hybrid anode material delivered reversible lithium storage capacities of 809, 765, 539, and 359âmAâhâgâ1 at current densities of 180, 450, 900, and 1800âmAâgâ1, respectively. The superior performance of CoFe2O4/MWCNTs hybrid materials could be ascribed to the synergistic pinning effect of the wintersweet-flower-like nanoarchitecture. This strategy could also be applied to synthesize other metal oxide/CNTs hybrid materials as high-capacity anode materials for lithium ion batteries.
Sun, B, Chen, Z, Kim, HS, Ahn, H & Wang, G 2011, 'MnO/C core-shell nanorods as high capacity anode materials for lithium-ion batteries', Journal of Power Sources, vol. 196, no. 6, pp. 3346-3349.View/Download from: Publisher's site
MnO/C core-shell nanorods were synthesized by an in situ reduction method using MnO2 nanowires as precursor and block copolymer F127 as carbon source. Field emission scanning electron microscopy and transmission electron microscopy analysis indicated that a thin carbon layer was coated on the surfaces of the individual MnO nanorods. The electrochemical properties were evaluated by cyclic voltammetry and galvanostatic charge-discharge techniques. The as-prepared MnO/C core-shell nanorods exhibit a higher specific capacity than MnO microparticles as anode material for lithium ion batteries.
Wang, Y, Sun, B, Park, J, Kim, W, Kim, H & Wang, G 2011, 'Morphology control and electrochemical properties of nanosize LiFePO4 cathode material synthesized by co-precipitation combined with in situ polymerization', Journal Of Alloys And Compounds, vol. 509, no. 3, pp. 1040-1044.View/Download from: Publisher's site
Nanosize carbon coated LiFePO4 cathode material was synthesized by in situ polymerization. The as-prepared LiFePO4 cathode material was systematically characterized by X-ray diffraction, thermogravimetric-differential scanning calorimetry, X-ray photo-electron spectroscopy, field-emission scanning electron microscopy, and transmission electron microscopy techniques. Field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) images revealed that the morphology of the LiFePO4 consists of primary particles (40-50 nm) and agglomerated secondary particles (100-110 nm). Each particle is evenly coated with an amorphous carbon layer, which has a thickness around 3-5 nm. The electrochemical properties were examined by cyclic voltammetry and charge-discharge testing. The as-prepared LiFePO4 can deliver an initial discharge capacity of 145 mAh/g, 150 mAh/g, and 134 mAh/g at 0.2 C, 1 C, and 2 C rates, respectively, and exhibits excellent cycling stability. At a higher C-rate (5 C) a slight capacity loss could be found. However after being charge-discharge at lower C-rates, LiFePO4 can be regenerated and deliver the discharge capacity of 145 mAh/g at 0.2 C. (C) 2010 Elsevier B.V. All rights reserved.
Sun, B, Horvat, J, Kim, H, Kim, W, Ahn, J & Wang, G 2010, 'Synthesis Of Mesoporous Alpha-Fe2O3 Nanostructures For Highly Sensitive Gas Sensors And High Capacity Anode Materials In Lithium Ion Batteries', Journal Of Physical Chemistry C, vol. 114, no. 44, pp. 18753-18761.View/Download from: Publisher's site
Mesoporous alpha-Fe2O3 materials were prepared in large quantity by the soft template synthesis method using the triblock copolymer surfactant F127 as the template. Nitrogen adsorption desorption isothermal measurements and transmission electron microsco
Wang, G, Wang, B, Park, J, Wang, Y, Sun, B & Yao, J 2009, 'Highly efficient and large-scale synthesis of graphene by electrolytic exfoliation', Carbon, vol. 47, no. 14, pp. 3242-3246.View/Download from: Publisher's site
Highly efficient and large-scale synthesis of graphene from graphite was produced by electrolytic exfoliation using poly(sodium-4-styrenesulfonate) as an effective electrolyte. Scanning and transmission electron microscopy, and atomic force microscopy confirmed the existence of monolayer graphene sheets and stacks containing a few graphene sheets. Raman spectroscopy demonstrated that the as-prepared graphene sheets have low defect content. Based on the measurement of FTIR spectra, the edge-to-face interaction (?? interaction) between the graphene surface and aromatic rings of poly(sodium-4-styrenesulfonate) could be primarily responsible for producing exfoliation of the graphite electrode to graphene during electrolysis. In contrast to micromechanical exfoliation, electrolytic exfoliation can be scaled up for large-scale and continuous graphene production.
Qiao, J, Sun, K, Zhang, N, Sun, B, Kong, J & Zhou, D 2007, 'Ni/YSZ and Ni-CeO2/YSZ anodes prepared by impregnation for solid oxide fuel cells', JOURNAL OF POWER SOURCES, vol. 169, no. 2, pp. 253-258.View/Download from: Publisher's site
Liu, H, Sun, B & Wang, G 2016, 'Advances in Electrochemical Energy Materials and Technologies' in Electrochemical Energy Advanced Materials and Technologies, CRC Press, USA, pp. 33-53.View/Download from: Publisher's site
Greenhouse gas emissions from consumption of fossil fuels by traditional vehicles are
major causes of global warming and worldwide climate change. Rechargeable batteries are
widely considered as the promising power source for the next generation of electric vehicles
in order to relieve our reliance on fossil fuels. The lithium ion battery is well recognized as
the best choice among all different electrochemical power sources, such as fuel cells, solar
cells, lead-acid, Nickel-Cadmium and Nickel metal hydride batteries. The research and
development (R&D) on the lithium ion batteries has progressed rapidly since it was first
commercialized in the 1990s. Rechargeable lithium ion batteries have revolutionized portable
electronic devices and have become the dominant power source for mobile phones, laptop
computers and digital cameras because of their high energy density.[1,2] However, the
charge/discharge process in lithium ion batteries at high current rates can cause a high level
of polarization for bulk materials and degrade the electrochemical properties of the batteries.
The development of electric vehicles or hybrid electric vehicles demands high power
batteries, which can operate under high current conditions. In following sections, we will
briefly introduce advances in materials and technologies for lithium ion batteries and lithium
Automotive Australia 2020 Cooperative Research Centre (AutoCRC),
Rail Manufacturing Cooperative Research Centre (RMCRC),
Changchun Institute of Applied Chemistry (CIAC), Chinese Academy of Sciences (CAS),
Eindhoven University of Technology,
The University of New South Wales
Justus Liebig University Giessen