2017. 09 – present: Centre for Clean Energy Technology, School of Mathematical and Physical Sciences, Faculty of Science, University of Technology, Sydney (UTS). (Postdoctoral research fellow)
2016. 08 – 2017. 08: Manufacturing Lindfield, Commonwealth Scientific and Industrial Research Organisation (CSIRO). (Joint program PhD candidate)
2013. 09 – 2017. 08: Centre for Clean Energy Technology, School of Mathematical and Physical Sciences, Faculty of Science, University of Technology, Sydney (UTS). (PhD candidate)
2012. 02 – 2013. 07: Centre for Clean Energy Technology, School of Mathematical and Physical Sciences, Faculty of Science, University of Technology, Sydney (UTS). (MSc)
2010. 10 – 2011. 07: Key Lab Organ Solids, Institute of Chemistry, Chinese Academy of Sciences (CAS). (Research Associate)
2007. 09- 2011. 07: School of Chemistry, Capital Normal University (CNU). (BSc)
Can supervise: YES
Functional organic materials (particular redox-enabled organic compounds) for lithium batteries including lithium-ion batteries and lithium-oxygen oxygen batteries
Xiong, P, Zhang, X, Wan, H, Wang, S, Zhao, Y, Zhang, J, Zhou, D, Gao, W, Ma, R, Sasaki, T & Wang, G 2019, 'Interface Modulation of Two-Dimensional Superlattices for Efficient Overall Water Splitting.', Nano letters, vol. 19, no. 7, pp. 4518-4526.View/Download from: UTS OPUS or Publisher's site
Molecular-scale modulation of interfaces between different unilamellar nanosheets in superlattices is promising for efficient catalytic activities. Here, three kinds of superlattices from alternate restacking of any two of the three unilamellar nanosheets of MoS2, NiFe-layered double hydroxide (NiFe-LDH), and graphene are systematically investigated for electrocatalytic water splitting. The MoS2/NiFe-LDH superlattice exhibits a low overpotential of 210 and 110 mV at 10 mA cm-2 for oxygen evolution reaction (OER) and alkaline hydrogen evolution reaction (HER), respectively, superior than MoS2/graphene and NiFe-LDH/graphene superlattices. High activity and stability toward the overall water splitting are also demonstrated on the MoS2/NiFe-LDH superlattice bifunctional electrocatalyst, outperforming the commercial Pt/C-RuO2 couple. This outstanding performance can be attributed to optimal adsorption energies of both HER and OER intermediates on the MoS2/NiFe-LDH superlattice, which originates from a strong electronic coupling effect at the heterointerfaces. These results herald the interface modulation of superlattices providing a promising approach for designing advanced electrocatalysts.
Zhang, F, Xiong, P, Guo, X, Zhang, J, Yang, W, Wu, W, Liu, H & Wang, G 2019, 'A nitrogen, sulphur dual-doped hierarchical porous carbon with interconnected conductive polyaniline coating for high-performance sodium-selenium batteries', Energy Storage Materials, vol. 19, pp. 251-260.View/Download from: UTS OPUS or Publisher's site
© 2019 Elsevier B.V. Sodium-selenium (Na-Se)battery has been emerging as a new rechargeable energy storage system with high capacity, low cost and high rate capability. However, the shuttling of polyselenides from the cathode to the anode causes dramatic capacity decay, severely impeding their practical applications. Herein, we report a combinational strategy of nitrogen and sulphur dual-doped hierarchical porous carbon with interconnected conductive polyaniline (PANI)coating to incorporate Se as stable cathodes (i-PANI@NSHPC/Se)for Na-Se batteries. Ex situ characterizations and density functional theory (DFT)calculations demonstrate that the i-PANI@NSHPC/Se cathode can provide both physical diffusion barrier and strong chemical affinity for polyselenides. In addition, the interconnected conductive polyaniline network enhances the conductivity for electrons and ions. With this strategy, the i-PANI@NSHPC/Se cathode delivered a high reversible capacity of 617 mAh g −1 after 200 cycles at 0.2C with a low capacity decay rate of 0.013% per cycle and an excellent rate capability at 20 C. Importantly, stable cycling performances were achieved with high capacities at different Se areal mass loadings (1.2, 2.3, 3.5 mg cm −2 ). This work could provide an efficient approach for developing Na-Se batteries with high active material mass loading, high rate capacity and long cycle life.
Sahu, TS, Choi, S, Jaumaux, P, Zhang, J, Wang, C, Zhou, D & Wang, G 2019, 'Squalene-derived sulfur-rich copolymer@ 3D graphene-carbon nanotube network cathode for high-performance lithium-sulfur batteries', Polyhedron, vol. 162, pp. 147-154.View/Download from: UTS OPUS or Publisher's site
© 2019 Elsevier Ltd Lithium-sulfur (Li-S) batteries with high theoretical energy density and low cost are considered a promising energy storage system. However, great challenges still remain in achieving high sulfur loading and long cycle life. Herein we report a well-designed sulfur-rich copolymer@ 3D graphene-carbon nanotubes (G-CNT) network cathode for high-performance Li-S batteries. The sulfur-rich copolymer (87.29% sulfur) synthesised by inverse vulcanization between two eco-friendly sources, sulfur and squalene, can greatly suppress the dissolution of sulfur and polusulfides due to the chemical confinement from the crosslinking of polysulfur chains with the squalene molecules. The interlinked Sp2 G-CNT network can not only further enhance the polysulfide entrapment capability, but also provide the composite with an 3D electrical conductive path as well as an eminent mechanical resilience towards the huge volume change of sulfur. The as-developed cathode can deliver a high specific capacity of 1265 mAh g−1 at 0.2C with excellent rate performance and cycling stability (782 mAh g−1 at after 300 cycles at 1C).
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.
Song, J, Guo, X, Zhang, J, Chen, Y, Zhang, C, Luo, L, Wang, F & Wang, G 2019, 'Rational design of free-standing 3D porous MXene/rGO hybrid aerogels as polysulfide reservoirs for high-energy lithium-sulfur batteries', Journal of Materials Chemistry A, vol. 7, no. 11, pp. 6507-6513.View/Download from: UTS OPUS or Publisher's site
© 2019 The Royal Society of Chemistry. Lithium-sulfur (Li-S) batteries with a high theoretical energy density are attracting increasing attention as promising candidates for next-generation energy storage systems. However, the insulating nature and undesirable shuttle effect of sulfur species dramatically impede their practical applications. Herein, a unique 3D porous Ti3C2Tx MXene/rGO (MX/G) hybrid aerogel is rationally designed and applied for the first time as a free-standing polysulfide reservoir to improve the overall performance of Li-S batteries. In this strategy, highly conductive MXene and rGO are integrated into a 3D interconnected porous aerogel structure with efficient 2D polar adsorption interfaces, enabling fast Li+/electron transport and strong chemical anchoring of lithium polysulfides as well as enhanced redox reaction kinetics. The robust MX/G aerogel electrodes deliver excellent electrochemical performances including a high capacity of 1270 mA h g-1 at 0.1C, an extended cycling life up to 500 cycles with a low capacity decay rate of 0.07% per cycle, and a high areal capacity of 5.27 mA h cm-2.
Wu, W, Zhao, Y, Li, S, He, B, Liu, H, Zeng, X, Zhang, J & Wang, G 2019, 'P doped MoS2 nanoplates embedded in nitrogen doped carbon nanofibers as an efficient catalyst for hydrogen evolution reaction.', Journal of colloid and interface science, vol. 547, pp. 291-298.View/Download from: UTS OPUS or Publisher's site
Two-dimensional (2D) molybdenum sulfide (MoS2) is considered as a promising catalyst for hydrogen evolution reaction (HER), originated from its abundant hydrogen evolution active sites. However, the HER performance of MoS2 is currently hindered by the limited exposed density of the active sites and low conductivity. Herein, we report a facile and scalable electrospinning technique to fabricate 2D MoS2 nanoplates doped with phosphorus within one-dimensional nitrogen doped-carbon nanofibers (NCNFs-MoS2|P) as a highly efficient HER catalyst. The space-confined growth with the presence of NCNFs avoided the stacking and aggregation of the MoS2 nanoplates, resulting in more exposed edge sites. The introduction of phosphorus atoms further activated the surface of MoS2 and enhanced the electron transfer. The overpotential of NCNFs-MoS2|P reached 98 mV at 10 mA cm-2, exhibiting excellent HER catalytic activity. Besides, almost no decay was observed after the stability test (5000 cycles or 20 h). The density functional calculations (DFT) elucidated that the incorporation of phosphorus atoms significantly improved the electrical conductivity and decreased the H adsorption energy barrier on MoS2, leading to a high catalytic performance of NCNFs-MoS2|P.
Zhang, J, Sade, H, Zhao, Y, Murdock, AT, Bendavid, A, Lellouche, J-P, Wang, G & Han, Z 2019, 'Conformal carbon coating on WS2 nanotubes for excellent electrochemical performance of lithium-ion batteries.', Nanotechnology, vol. 30, no. 3, pp. 035401-035401.View/Download from: UTS OPUS or Publisher's site
WS2 nanotubes with carbon coatings in a core-shell structure (i.e. WS2@C) are synthesized through a facile method based on the Lewis acid-activated thioglycosylation chemistry. The obtained WS2@C shows a conformal coverage of conductive amorphous carbon on the surface of WS2 after thermal treatment, with the thickness of carbon layer being controlled by adjusting the molar ratios of saccharide to nanotube during the synthesis process. When applied in lithium-ion batteries, the WS2@C structures show higher reversible capacity of 638 mAh g-1 at a current density of 500 mA g-1 and significantly improved cycling stability as compared to the pristine WS2 nanotubes. Post-mortem examinations of the electrode materials reveal that the carbon coatings could preserve the morphology of WS2 nanotubes and assist in forming stable solid electrolyte interface layers, leading to enhanced cycling stability. As such, the WS2@C structures show great potential in the application of lithium-ion batteries for achieving excellent electrochemical performances.
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: UTS OPUS or 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, Y, Wang, S, Liu, H, Guo, X, Zeng, X, Wu, W, Zhang, J & Wang, G 2019, 'Porous Mo2C nanorods as an efficient catalyst for the hydrogen evolution reaction', Journal of Physics and Chemistry of Solids, vol. 132, pp. 230-235.View/Download from: UTS OPUS or Publisher's site
© 2019 Elsevier Ltd Generate hydrogen fuel from electrochemical water splitting has been considered as a promising approach. However, to obtain the low-cost and high performance catalysts towards hydrogen evolution reaction (HER)which can be applied in both alkaline and acid solution remains a challenge. Herein, we synthesized an active and stable HER catalyst composed of Mo2C nanocrystals embedded in the nanocarbon layers (Mo2C@C)by using MoO3 nanorods as precursor. Benefiting from the porous one dimensional structure and ultrafine Mo2C nanocrystals, Mo2C@C exhibits high HER catalytic activity for 10 mA cm−2 with the overpotential of 119 mV in 1 M KOH solution and 170 mV in 0.5 M H2SO4 solution, respectively. Moreover, Mo2C@C displays long durability during the HER process with almost no decay and maintains the porous one dimensional architecture after the HER stability test. This study offers the guideline for the further design and fabrication of the nanostructured HER electrocatalysts in wide pH range.
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.
Zhao, Y, Zhang, J, Wu, W, Guo, X, Xiong, P, Liu, H & Wang, G 2018, 'Cobalt-doped MnO2 ultrathin nanosheets with abundant oxygen vacancies supported on functionalized carbon nanofibers for efficient oxygen evolution', Nano Energy, vol. 54, pp. 129-137.View/Download from: UTS OPUS or Publisher's site
© 2018 Elsevier Ltd Developing low-cost and efficient catalysts for oxygen evolution reactions (OER) with both excellent activity and robust stability remains a great challenge. Herein, we report a facile spontaneous redox reaction to grow cobalt-doped MnO2 ultrathin nanosheets in situ with abundant oxygen vacancies vertically aligned on cobalt/nitrogen co-functionalized carbon nanofibers (Co-MnO2|OV) as an efficient OER catalyst. It is confirmed that metallic cobalt plays a critical role in the formation of long and ultrathin MnO2 nanosheets during the redox reaction. Furthermore, the cobalt ions doped into MnO2 significantly enhance the catalytic activity of MnO2 nanosheets. Benefiting from the collaborative advantages of doping strategy, fast charge transfer kinetics and strong synergistic coupling effects, Co-MnO2|OV composites exhibit an excellent catalytic activity and a good durability for electrochemical water oxidation, reaching 10 mA cm−2 at an overpotential of 279 mV. According to the density functional theory (DFT) calculations, the enhanced catalytic activity mainly originates from a better conductivity and the decreased adsorption energy barrier of OH- on the O sites neighboring the doped Co and oxygen vacancies. Our findings suggest that the control over the structure and composition of the materials can achieve highly efficient oxygen evolution electrocatalysts.
Guo, X, Zhang, J, Song, J, Wu, W, Liu, H & Wang, G 2018, 'MXene encapsulated titanium oxide nanospheres for ultra-stable and fast sodium storage', Energy Storage Materials, vol. 14, pp. 306-313.View/Download from: UTS OPUS or Publisher's site
© 2018 Sodium-ion batteries with high power density present tremendous potential for large-scale energy storage applications. However, it remains a big challenge to develop suitable anode materials for ultrafast and highly reversible sodium ion storage. Herein, for the first time, we report a novel strategy to fabricate highly conductive MXene Ti3C2Txencapsulated titanium oxide spheres (TiO2@Ti3C2Tx) as an excellent anode material for sodium-ion batteries. The MXene layers significantly improve the electronic conductivity of the whole electrode and protect the structural integrity of the TiO2spheres from electrochemical pulverization, which hence contributes to the formation of a stable solid-electrolyte interface. Meanwhile, the pseudocapacitance of the as-fabricated TiO2@Ti3C2Txcomposites enables high-rate capability and long cycle life in sodium-ion batteries. As a result, the hybrid electrode delivers a high reversible capacity of 116 mAh g-1at 960 mA g-1up to 5000 cycles. By coupling with a NaCrO2cathode, a prototype Na-ion full cell achieved a capacity of 103.4 mAh g-1at 960 mA g-1and an excellent cycling performance with 73.5% capacity retention after 1000 cycles.
Song, J, Zhang, C, Guo, X, Zhang, J, Luo, L, Liu, H, Wang, F & Wang, G 2018, 'Entrapping polysulfides by using ultrathin hollow carbon sphere-functionalized separators in high-rate lithium-sulfur batteries', Journal of Materials Chemistry A, vol. 6, no. 34, pp. 16610-16616.View/Download from: UTS OPUS or Publisher's site
© 2018 The Royal Society of Chemistry. Lithium-sulfur batteries (LSBs) have been regarded as the most promising technology for next generation energy storage systems owing to their high energy density and low cost. However, the undesirable shuttle effect and low utilization of sulfur caused by dissolution and migration of polysulfide intermediates greatly restrict their practical application. Herein, we report a functional separator modified with novel ultrathin hollow carbon spheres (UHCSs) to improve the overall performance of LSBs and demonstrate for the first time that nonporous hollow structured carbon materials are ideal candidates for modifying the separator due to their unique properties. The ultrathin and nonporous shell of the coated UHCSs can act as a physical and a chemical barrier to effectively entrap lithium polysulfides owing to fewer diffusion sites. The UHCSs can also enhance the electron transfer for sulfur and accommodate the large volume change of sulfur as upper current collectors. When applying such UHCSs functionalized separators, the LSBs achieved a significantly improved electrochemical performance including a high capacity of 1346.3 mA h g-1 at 0.2C and high rate capability with a discharge capacity of 458 mA h g-1 even at 5C upon 1000 cycles.
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: UTS OPUS or 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: UTS OPUS or 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.
Zhang, J, Zhao, Y, Guo, X, Chen, C, Dong, CL, Liu, RS, Han, CP, Li, Y, Gogotsi, Y & Wang, G 2018, 'Single platinum atoms immobilized on an MXene as an efficient catalyst for the hydrogen evolution reaction', Nature Catalysis, vol. 1, no. 12, pp. 985-992.View/Download from: UTS OPUS or Publisher's site
© 2018, The Author(s), under exclusive licence to Springer Nature Limited. Single-atom catalysts offer a pathway to cost-efficient catalysis using the minimal amount of precious metals. However, preparing and keeping them stable during operation remains a challenge. Here we report the synthesis of double transition metal MXene nanosheets—Mo 2 TiC 2 T x , with abundant exposed basal planes and Mo vacancies in the outer layers—by electrochemical exfoliation, enabled by the interaction between protons and the surface functional groups of Mo 2 TiC 2 T x . The as-formed Mo vacancies are used to immobilize single Pt atoms, enhancing the MXene's catalytic activity for the hydrogen evolution reaction. The developed catalyst exhibits a high catalytic ability with low overpotentials of 30 and 77 mV to achieve 10 and 100 mA cm −2 and a mass activity about 40 times greater than the commercial platinum-on-carbon catalyst. The strong covalent interactions between positively charged Pt single atoms and the MXene contribute to the exceptional catalytic performance and stability.
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
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: UTS OPUS or 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.
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: UTS OPUS or 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: UTS OPUS or 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: UTS OPUS or 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.
Zhao, Y, Zhang, J, Guo, X, Fan, H, Wu, W, Liu, H & Wang, G 2017, 'Fe3C@nitrogen doped CNT arrays aligned on nitrogen functionalized carbon nanofibers as highly efficient catalysts for the oxygen evolution reaction', Journal of Materials Chemistry A, vol. 5, no. 37, pp. 19672-19679.View/Download from: UTS OPUS or Publisher's site
© 2017 The Royal Society of Chemistry. Fe 3 C based catalysts are found to be one of the most promising electrocatalysts for the oxygen evolution reaction (OER). Herein, we report on a nanoarchitectured material composed of Fe 3 C nanoparticles encapsulated at the tip of nitrogen-enriched carbon nanotubes (NCNTs), which are aligned on one dimensional (1D) nitrogen-doped carbon nanofibers (Fe 3 C@NCNTs-NCNFs) by a scalable electrospinning technique, as a high performance OER catalyst. The unique 3D hierarchical architecture of Fe 3 C@NCNTs-NCNFs leads to highly exposed active sites, enhanced electron transfer properties and strong synergistic coupled effects. Fe 3 C@NCNTs-NCNFs exhibit an outstanding catalytic performance with a high current density (10 mA cm -2 at an overpotential of 284 mV), a low Tafel slope (56 mV dec -1 ), a low charge transfer resistance and strong durability in 1 M KOH solution. The electrochemical evaluation demonstrates that the Fe 3 C@NCNTs-NCNF composite is a promising electrocatalyst for the OER in alkaline solution.
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
Wang, Y, Kretschmer, K, Zhang, J, Mondal, AK, Guo, X & Wang, G 2016, 'Organic sodium terephthalate@graphene hybrid anode materials for sodium-ion batteries', RSC ADVANCES, vol. 6, no. 62, pp. S7098-S7102.View/Download from: UTS OPUS or 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: UTS OPUS or Publisher's site
Zhao, Y, Zhang, J, Li, K, Ao, Z, Wang, C, Liu, H, Sun, K & Wang, G 2016, 'Electrospun cobalt embedded porous nitrogen doped carbon nanofibers as an efficient catalyst for water splitting', JOURNAL OF MATERIALS CHEMISTRY A, vol. 4, no. 33, pp. 12818-12824.View/Download from: Publisher's site
Su, D, Zhang, J, Dou, S & Wang, G 2015, 'Polypyrrole hollow nanospheres: stable cathode materials for sodium-ion batteries', CHEMICAL COMMUNICATIONS, vol. 51, no. 89, pp. 16092-16095.View/Download from: UTS OPUS or Publisher's site
Xie, X, Ao, Z, Su, D, Zhang, J & Wang, G 2015, 'MoS2/Graphene Composite Anodes with Enhanced Performance for Sodium-Ion Batteries: The Role of the Two-Dimensional Heterointerface', ADVANCED FUNCTIONAL MATERIALS, vol. 25, no. 9, pp. 1393-1403.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: UTS OPUS or Publisher's site
Xie, X, Su, D, Zhang, J, Chen, S, Mondal, AK & Wang, G 2015, 'A comparative investigation on the effects of nitrogen-doping into graphene on enhancing the electrochemical performance of SnO2/graphene for sodium-ion batteries', NANOSCALE, vol. 7, no. 7, pp. 3164-3172.View/Download from: UTS OPUS or 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: UTS OPUS or 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.
Zhao, Y, Xie, X, Zhang, J, Liu, H, Ahn, HJ, Sun, K & Wang, G 2015, 'MoS2 Nanosheets Supported on 3D Graphene Aerogel as a Highly Efficient Catalyst for Hydrogen Evolution.', Chemistry (Weinheim an der Bergstrasse, Germany), vol. 21, no. 45, pp. 15908-15913.View/Download from: Publisher's site
The development of efficient catalysts for electrochemical hydrogen evolution is essential for energy conversion technologies. Molybdenum disulfide (MoS2 ) has emerged as a promising electrocatalyst for hydrogen evolution reaction, and its performance greatly depends on its exposed edge sites and conductivity. Layered MoS2 nanosheets supported on a 3D graphene aerogel network (GA-MoS2 ) exhibit significant catalytic activity in hydrogen evolution. The GA-MoS2 composite displays a unique 3D architecture with large active surface areas, leading to high catalytic performance with low overpotential, high current density, and good stability.
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: UTS OPUS or 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: UTS OPUS or Publisher's site
Mondal, AK, Su, D, Chen, S, Zhang, J, Ung, A & Wang, G 2014, 'Microwave-assisted synthesis of spherical beta-Ni(OH)(2) superstructures for electrochemical capacitors with excellent cycling stability', CHEMICAL PHYSICS LETTERS, vol. 610, pp. 115-120.View/Download from: UTS OPUS or Publisher's site
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: UTS OPUS or 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: UTS OPUS or 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.
Xie, X, Su, D, Chen, S, Zhang, J, Dou, S & Wang, G 2014, 'SnS2 Nanoplatelet@Graphene Nanocomposites as High-Capacity Anode Materials for Sodium-Ion Batteries', Chemistry An Asian Journal, vol. 9, pp. 1611-1617.View/Download from: Publisher's site
Na-ion batteries have been attracting intensive investigations as a possible alternative to Li-ion batteries. Herein, we report the synthesis of SnS2 nanoplatelet@graphene nanocomposites by using a morphology-controlled hydrothermal method. The asprepared SnS2/graphene nanocomposites present a unique two-dimensional platelet-on-sheet nanoarchitecture, which has been identified by scanning and transmission electron microscopy. When applied as the anode material for Na-ion batteries, the SnS2/graphene nanosheets achieved a high reversible specific sodium-ion storage capacity of 725 mAhg1, stable cyclability, and an enhanced high-rate capability. The improved electrochemical performance for reversible sodium-ion storage could be ascribed to the synergistic effects of the SnS2 nanoplatelet/graphene nanosheets as an integrated hybrid nanoarchitecture, in which the graphene nanosheets provide electronic conductivity and cushion for the active SnS2 nanoplatelets during Na-ion insertion and extraction processes.
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: UTS OPUS or 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: UTS OPUS or 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: UTS OPUS or 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
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: UTS OPUS or 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.
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: UTS OPUS or 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.