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Full-Text Articles in Physical Sciences and Mathematics

A Germanium/Single-Walled Carbon Nanotube Composite Paper As A Free-Standing Anode For Lithium-Ion Batteries, Jun Wang, Jiazhao Wang, Ziqi Sun, Xuanwen Gao, Chao Zhong, Shulei Chou, Hua-Kun Liu Jan 2014

A Germanium/Single-Walled Carbon Nanotube Composite Paper As A Free-Standing Anode For Lithium-Ion Batteries, Jun Wang, Jiazhao Wang, Ziqi Sun, Xuanwen Gao, Chao Zhong, Shulei Chou, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Paper-like free-standing germanium (Ge) and single-walled carbon nanotube (SWCNT) composite anodes were synthesized by the vacuum filtration of Ge/SWCNT composites, which were prepared by a facile aqueous-based method. The samples were characterized by X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy. Electrochemical measurements demonstrate that the Ge/SWCNT composite paper anode with the weight percentage of 32% Ge delivered a specific discharge capacity of 417 mA h g−1 after 40 cycles at a current density of 25 mA g−1, 117% higher than the pure SWCNT paper anode. The SWCNTs not only function as a flexible mechanical support for …


Cuo Single Crystal With Exposed {001} Facets-A Highly Efficient Material For Gas Sensing And Li-Ion Battery Applications, Dawei Su, Xiuqiang Xie, S X. Dou, Guoxiu Wang Jan 2014

Cuo Single Crystal With Exposed {001} Facets-A Highly Efficient Material For Gas Sensing And Li-Ion Battery Applications, Dawei Su, Xiuqiang Xie, S X. Dou, Guoxiu Wang

Australian Institute for Innovative Materials - Papers

Single crystal copper oxide nanoplatelets with a high percentage of {001} facets were synthesized by a facile hydrothermal approach. The as-prepared materials were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, and high resolution transmission microscopy. Via density functional theory calculations, it was found that the {001} facets are active crystal planes. When the single crystal CuO nanoplatelets were applied as an anode material in Li-ion batteries, they demonstrated outstanding electrochemical performance with high lithium storage capacity, satisfactory cyclability, and excellent high rate capacity. When used as a sensing material in gas sensors, they exhibited …


Mesoporous Hexagonal Co3o4 For High Performance Lithium Ion Batteries, Dawei Su, Xiuqiang Xie, Paul Munroe, S X. Dou, Guoxiu Wang Jan 2014

Mesoporous Hexagonal Co3o4 For High Performance Lithium Ion Batteries, Dawei Su, Xiuqiang Xie, Paul Munroe, S X. Dou, Guoxiu Wang

Australian Institute for Innovative Materials - Papers

Mesoporous Co3O4 nanoplates were successfully prepared by the conversion of hexagonal beta-Co(OH)(2) nanoplates. TEM, HRTEM and N-2 sorption analysis confirmed the facet crystal structure and inner mesoporous architecture. When applied as anode materials for lithium storage in lithium ion batteries, mesoporous Co3O4 nanocrystals delivered a high specific capacity. At 10 degrees C current rate, as-prepared mesoporous Co3O4 nanoplates delivered a specific capacity of 1203 mAh/g at first cycle and after 200 cycles it can still maintain a satisfied value (330 mAh/g). Fromex-situ TEM, SAED and FESEM observation, it was found that mesoporous Co3O4 nanoplates were reduced to Li2O and Co …


Study On Vanadium Substitution To Iron In Li2fep 2o7 As Cathode Material For Lithium-Ion Batteries, Jiantie Xu, Shulei Chou, Qinfen Gu, M F. Md Din, Hua-Kun Liu, S X. Dou Jan 2014

Study On Vanadium Substitution To Iron In Li2fep 2o7 As Cathode Material For Lithium-Ion Batteries, Jiantie Xu, Shulei Chou, Qinfen Gu, M F. Md Din, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

A series of Li2Fe1-3x/2VxP 2O7 (x = 0, 0.025, 0.05, 0.075, and 0.1) cathode materials for LIBs were prepared by the sol-gel method. Structural characterization of Li2Fe1-3x/2VxP2O7 (x = 0, 0.025, 0.05, 0.075, and 0.1) samples was conducted by synchrotron X-ray diffraction. The morphology and oxidation states of Fe2+ and V 3+ in the Li2Fe1-3x/2VxP 2O7 samples were confirmed by scanning electron microscopy and magnetic susceptibility measurements, respectively. The electrochemical measurements indicated that Li2Fe1-3x/2VxP 2O7 (x = 0.025) delivered the higher reversible capacity of 79.9 mAh g-1 at 1 C in the voltage range of 2.0 - 4.5 V with …


Novel Germanium/Polypyrrole Composite For High Power Lithium-Ion Batteries, Xuanwen Gao, Wenbin Luo, Chao Zhong, David Wexler, Shulei Chou, Hua-Kun Liu, Zhicong Shi, Guohua Chen, Kiyoshi Ozawa, Jiazhao Wang Jan 2014

Novel Germanium/Polypyrrole Composite For High Power Lithium-Ion Batteries, Xuanwen Gao, Wenbin Luo, Chao Zhong, David Wexler, Shulei Chou, Hua-Kun Liu, Zhicong Shi, Guohua Chen, Kiyoshi Ozawa, Jiazhao Wang

Australian Institute for Innovative Materials - Papers

Nano-Germanium/polypyrrole composite has been synthesized by chemical reduction method in aqueous solution. The Ge nanoparticles were directly coated on the surface of the polypyrrole. The morphology and structural properties of samples were determined by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Thermogravimetric analysis was carried out to determine the polypyrrole content. The electrochemical properties of the samples have been investigated and their suitability as anode materials for the lithium-ion battery was examined. The discharge capacity of the Ge nanoparticles calculated in the Ge-polypyrrole composite is 1014 mAh g-1 after 50 cycles at 0.2 C rate, which is …


Na3v2(Po4)3 Particles Partly Embedded In Carbon Nanofibers With Superb Kinetics For Ultra-High Power Sodium Ion Batteries, Junghoon Yang, Dongwook Han, Mi Ru Jo, Kyeongse Song, Yongil Kim, Shulei Chou, Hua-Kun Liu, Yong-Mook Kang Jan 2014

Na3v2(Po4)3 Particles Partly Embedded In Carbon Nanofibers With Superb Kinetics For Ultra-High Power Sodium Ion Batteries, Junghoon Yang, Dongwook Han, Mi Ru Jo, Kyeongse Song, Yongil Kim, Shulei Chou, Hua-Kun Liu, Yong-Mook Kang

Australian Institute for Innovative Materials - Papers

We here describe the extraordinary performance of NASICON Na3V2(PO4)3-carbon nanofiber (NVP-CNF) composites with ultra-high power and excellent cycling performance. NVP-CNFs are composed of CNFs at the center part and partly embedded NVP nanoparticles in the shell. We first report this unique morphology of NVP-CNFs for the electrode material of secondary batteries as well as for general energy conversion materials. Our NVP-CNFs show not only a high discharge capacity of approx. 88.9 mA h g-1 even at a high current density of 50 C but also approx. 93% cyclic retention property after …


Synthesis And Electrochemical Properties Of Wo3/C For Lithium Ion Batteries, Hong Gao, Shuijin S. Yang, Chuanqi Feng, Jiazhao Wang, Zaiping Guo Jan 2014

Synthesis And Electrochemical Properties Of Wo3/C For Lithium Ion Batteries, Hong Gao, Shuijin S. Yang, Chuanqi Feng, Jiazhao Wang, Zaiping Guo

Australian Institute for Innovative Materials - Papers

WO3/C nanorods were prepared by a combination of hydrothermal synthesis method and the solid phase reaction method, using (NH4)10H2(W2O7)6, H2C2O4·2H2O and glucose(carbon source) as raw materials. The effects of different proportions of glucose on the morphologies and electrochemical properties of the final products were systematically investigated. The results showed that the WO3/C nanorods prepared with the 10 wt.% glucose as carbon source exhibited the highest reversible specific capacity (807 mAh g-1) at current density …


Pristine Organo-Imido Polyoxometalates As An Anode For Lithium Ion Batteries, Rao Naumaan Nasim Khan, Nasir Mahmood, Chunlin Lv, Guohui Sima, Jin Zhang, Jian Hao, Yanglong Hou, Yongge Wei Jan 2014

Pristine Organo-Imido Polyoxometalates As An Anode For Lithium Ion Batteries, Rao Naumaan Nasim Khan, Nasir Mahmood, Chunlin Lv, Guohui Sima, Jin Zhang, Jian Hao, Yanglong Hou, Yongge Wei

Australian Institute for Innovative Materials - Papers

Here we have designed a strategy to improve the electronic conductivities of polyoxometalates (POMs) via property-oriented organic grafting for use in lithium-ion batteries (LIBs). POMs usually exhibit limited electronic conductivity that hinders their use in electronic applications. Organic grafting of POMs defines a valuable path for improving electronic conductivities of POMs, due to the enhanced metal to ligand charge transfer (MLCT) via d-π electronic interactions, and results in their feasible application in LIBs. Comparative practical and theoretical study of the effect of functional groups revealed that grafting of the remote electron withdrawing group (-SCN) on POMs via organo-imidoylization along with …


Zno-Doped Lifepo4 Cathode Material For Lithium-Ion Battery Fabricated By Hydrothermal Method, Yemin Hu, Jun Yao, Zhe Zhao, Mingyuan Zhu, Ying Li, Hongming Jin, Huijun Zhao, Jiazhao Wang Jan 2013

Zno-Doped Lifepo4 Cathode Material For Lithium-Ion Battery Fabricated By Hydrothermal Method, Yemin Hu, Jun Yao, Zhe Zhao, Mingyuan Zhu, Ying Li, Hongming Jin, Huijun Zhao, Jiazhao Wang

Australian Institute for Innovative Materials - Papers

LiFePO4 particles doped with zinc oxide was synthesized via a hydrothermal route and used as cathode material for lithium-ion battery. Sample of preferable shape and structure was obtained by a concise and efficient process. ZnO doping into the LiFePO4 matrix was positively confirmed by the results of X-ray diffraction (XRD); high-resolution transmission electron microscopy (HRTEM); energy dispersive spectrometer (EDS), and X-ray photoelectron spectroscopy (XPS). LiFePO4 doped with ZnO tends to form nanometer-size and homogeneous particles, which can improve markedly the performance and stability of charge-discharge cycle. A specific discharge capacity of ZnO-doped LiFePO4 at 132.3 mAh g-1 was achieved, with …


Simply Mixed Commercial Red Phosphorus And Carbon Nanotube Composite With Exceptionally Reversible Sodium-Ion Storage, Wei-Jie Li, Shulei Chou, Jia-Zhao Wang, Hua-Kun Liu, S X. Dou Jan 2013

Simply Mixed Commercial Red Phosphorus And Carbon Nanotube Composite With Exceptionally Reversible Sodium-Ion Storage, Wei-Jie Li, Shulei Chou, Jia-Zhao Wang, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

Recently, sodium ion batteries (SIBs) have been given intense attention because they are the most promising alternative to lithium ion batteries for application in renewable power stations and smart grid, owing to their low cost, their abundant natural resources, and the similar chemistry of sodium and lithium. Elemental phosphorus (P) is the most promising anode materials for SIBs with the highest theoretical capacity of 2596 mA h g-1, but the commercially available red phosphorus cannot react with Na reversibly. Here, we report that simply hand-grinding commercial microsized red phosphorus and carbon nanotubes (CNTs) can deliver a reversible capacity of 1675 …


Hollow Structured Li3vo4 Wrapped With Graphene Nanosheets In Situ Prepared By One-Pot Template-Free Method As An Anode For Lithium-Ion Batteries, Yi Shi, Jia-Zhao Wang, Shulei Chou, David Wexler, Hui-Jun Li, Kiyoshi Ozawa, Hua-Kun Liu, Yu-Ping Wu Jan 2013

Hollow Structured Li3vo4 Wrapped With Graphene Nanosheets In Situ Prepared By One-Pot Template-Free Method As An Anode For Lithium-Ion Batteries, Yi Shi, Jia-Zhao Wang, Shulei Chou, David Wexler, Hui-Jun Li, Kiyoshi Ozawa, Hua-Kun Liu, Yu-Ping Wu

Australian Institute for Innovative Materials - Papers

To explore good anode materials of high safety, high reversible capacity, good cycling, and excellent rate capability, a Li3VO4 microbox with wall thickness of 40 nm was prepared by a one-pot and template-free in situ hydrothermal method. In addition, its composite with graphene nanosheets of about six layers of graphene was achieved. Both of them, especially the Li3VO4/graphene nanosheets composite, show superior electrochemical performance to the formerly reported vanadium-based anode materials. The composite shows a reversible capacity of 223 mAh g−1 even at 20C (1C = 400 mAh g−1). After 500 cycles at 10C there is no evident capacity fading.


Simple Synthesis Of Yolk-Shelled Znco2o4 Microspheres Towards Enhancing The Electrochemical Performance Of Lithium-Ion Batteries In Conjunction With A Sodium Carboxymethyl Cellulose Binder, Jingfa Li, Jiazhao Wang, David Wexler, Dongqi Shi, Jianwen Liang, Hua-Kun Liu, Shenglin Xiong, Yitai Qian Jan 2013

Simple Synthesis Of Yolk-Shelled Znco2o4 Microspheres Towards Enhancing The Electrochemical Performance Of Lithium-Ion Batteries In Conjunction With A Sodium Carboxymethyl Cellulose Binder, Jingfa Li, Jiazhao Wang, David Wexler, Dongqi Shi, Jianwen Liang, Hua-Kun Liu, Shenglin Xiong, Yitai Qian

Australian Institute for Innovative Materials - Papers

Mixed metal oxides have been attracting more and more attention recently because of their advantages and superiorities, which can improve the electrochemical performance of single metal oxides. These advantages include structural stability, good electronic conductivity, and reversible capacity. In this work, uniform yolk-shelled ZnCo2O4 microspheres were synthesized by pyrolysis of ZnCo-glycolate microsphere precursors which were prepared via a simple refluxing route without any precipitant or surfactant. The formation process of the yolk-shelled microsphere structure during the thermal decomposition of ZnCo-glycolate is discussed, which is mainly based on the heterogeneous contraction caused by non-equilibrium heat treatment. The performances of the as-prepared …


Nanocomposites Of Silicon And Carbon Derived From Coal Tar Pitch: Cheap Anode Materials For Lithium-Ion Batteries With Long Cycle Life And Enhanced Capacity, Yun-Xiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou Jan 2013

Nanocomposites Of Silicon And Carbon Derived From Coal Tar Pitch: Cheap Anode Materials For Lithium-Ion Batteries With Long Cycle Life And Enhanced Capacity, Yun-Xiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

From energy and environmental consideration, an industrial waste product, coal tar pitch (CTP), is used as the carbon source for Si/AC composite. We exploited a facile sintering method to largely scale up Si/amorphous carbon nanocomposite. The composites with 20 wt.% silicon with PVdF binder exhibited stable lithium storage ability for prolonged cycling. The composite anode delivered a capacity of 400.3 mAh g−1 with a high capacity retention of 71.3% after 1000 cycles. Various methods are used to investigate the reason for the outstanding cyclability. The results indicate that the silicon nanoparticles are wrapped by amorphous SiOx and AC in Si/AC …


Applications Of Voltammetric Ion Selective Electrodes To Complex Matrices, Alexander R. Harris, Jie Zhang, Robert W. Cattrall, Alan M. Bond Jan 2013

Applications Of Voltammetric Ion Selective Electrodes To Complex Matrices, Alexander R. Harris, Jie Zhang, Robert W. Cattrall, Alan M. Bond

Australian Institute for Innovative Materials - Papers

The practical application of two different voltammetric ion selective electrodes (VISE) to measure ion activity in complex solutions has been explored. 7,7,8,8-tetracyanoquinodimethane (TCNQ) and tetrathiafulvalene (TTF) microcrystals adhered to an electrode surface act as a low selectivity voltammetric ion sensor. Resistance drop effects and pH artifacts were minimised by the addition of an "innocent" supporting electrolyte (buffer) to the analyte solution. In this format, addition of an ionophore to improve selectivity resulted in a reduction in current magnitude, due to competition for the ion. In contrast, voltammetry of a thin film containing a redox active species, electrolyte, ionophore and membrane …


Free-Standing Single-Walled Carbon Nanotube/Sno2 Anode Paper For Flexible Lithium-Ion Batteries, Lukman Noerochim, Jia-Zhao Wang, Shulei Chou, David Wexler Jan 2012

Free-Standing Single-Walled Carbon Nanotube/Sno2 Anode Paper For Flexible Lithium-Ion Batteries, Lukman Noerochim, Jia-Zhao Wang, Shulei Chou, David Wexler

Australian Institute for Innovative Materials - Papers

Free-standingsingle-walledcarbonnanotube/SnO2 (SWCNT/SnO2) anodepaper was prepared by vacuum filtration of SWCNT/SnO2 hybrid material which was synthesized by the polyol method. From field emission scanning electron microscopy and transmission electron microscopy, the CNTs form a three-dimensional nanoporous network, in which ultra-fine SnO2 nanoparticles, which had crystallite sizes of less than 5 nm, were distributed, predominately as groups of nanoparticles on the surfaces of singlewalled CNT bundles. Electrochemical measurements demonstrated that the anodepaper with 34 wt.% SnO2 had excellent cyclic retention, with the high specific capacity of 454 mAh g−1 beyond 100 cycles at a current …


Lifepo4-Fe2p-C Composite Cathode: An Environmentally Friendly Promising Electrode Material For Lithium-Ion Battery, M. Mahfuzur Rahman, Jiazhao Wang, Rong Zeng, David Wexler, Hua-Kun Liu Jan 2012

Lifepo4-Fe2p-C Composite Cathode: An Environmentally Friendly Promising Electrode Material For Lithium-Ion Battery, M. Mahfuzur Rahman, Jiazhao Wang, Rong Zeng, David Wexler, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

In this investigation, the synthesis strategy is involved the creation of LiFePO4-Fe2P-C composites with a porous conductive architecture, which includes distinct regions or clusters containing antiferromagnetic LiFePO4 in close proximity to ferromagnetic Fe2P. The microstructure is achieved by using a simple ultra-fast solvent assisted manual grinding method, combined with solid state reaction, which can replace the time-consuming high energy ball milling method. The crystalline structure, morphology, and electrochemical characterization of the synthesised product are investigated systematically. The electrochemical performance is outstanding, especially the high C rate. The composite cathode is found to display specific capacity of 167 mAh g-1 at …


Irradiation Si On Carbon Nanotube Paper As A Flexible Anode Material For Lithium-Ion Batteries, Shulei Chou, Mihail Ionescu, Jia-Zhao Wang, Brad Winton, Hua-Kun Liu Jan 2012

Irradiation Si On Carbon Nanotube Paper As A Flexible Anode Material For Lithium-Ion Batteries, Shulei Chou, Mihail Ionescu, Jia-Zhao Wang, Brad Winton, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Silicon single walled carbon nanotube composite paper was modified by low energy ion implantation using 5i to obtain a flexible composite paper. Raman and FE-SEM results show that structure of SWCNT could be destroyed by the implantation. Electrochemical measurements display that the implanted SI can improve the specific capacity and the reversible capacity of CNT paper. After 50 cycles, the specific capacity of 5Hmplanted CNT paper is 30 per cent higher than the pristine CNT.


Position Preference And Diffusion Path Of An Oxygen Ion In Apatite-Type Lanthanum Silicate La9.33si6o26: A Density Functional Study, Ting Liao, Taizo Sasaki, Shigeru Suehara, Ziqi Sun Jan 2011

Position Preference And Diffusion Path Of An Oxygen Ion In Apatite-Type Lanthanum Silicate La9.33si6o26: A Density Functional Study, Ting Liao, Taizo Sasaki, Shigeru Suehara, Ziqi Sun

Australian Institute for Innovative Materials - Papers

Using density functional theory, we investigated the position preference and diffusion mechanisms of interstitial oxygen ions in lanthanum silicate La9.33Si6O26, which is an apatite-structured oxide and a promising candidate electrolyte material for solid oxide fuel cells. The reported lanthanum vacancies were explicitly taken into account by theoretically determining their arrangement with a supercell model. The most stable structures and the formation energies of oxygen interstitials were determined for each charged state. It was found that the double-negatively charged state is stable over a wide range of the Fermi level, and that the excess oxygen …


Bi-2212 Based Anode Materials For Li-Ion Batteries, Matthew Lindsay, Hua-Kun Liu Jan 2007

Bi-2212 Based Anode Materials For Li-Ion Batteries, Matthew Lindsay, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

A number of studies have previously examined the insertion of lithium into superconductor Bi2Sr2CaCu2O8+δ(Bi-2212) materials. A maximum lithium uptake of two moles of lithium per mole of Bi-2212 was reported amongst these studies which corresponds to a capacity of 60 mAh/g. Two Bi-2212 materials are examined here an undoped Bi2Sr2CaCu2O8+δ and doped Bi2Sr2Ca0.3Y0.7Cu2O8 material. Both materials exhibitied a capacity of over 60 mAh/g in both the as produced stated and whn subjected to further …


A Study On The Charge-Discharge Mechanism Of Co3o4 As An Anode For The Li Ion Secondary Battery, Yong-Mook Kang, Min-Sang Song, Jin-Ho Kim, Hyun-Seok Kim, Min-Sik Park, Jai-Young Lee, Hua-Kun Liu, S X. Dou Jan 2005

A Study On The Charge-Discharge Mechanism Of Co3o4 As An Anode For The Li Ion Secondary Battery, Yong-Mook Kang, Min-Sang Song, Jin-Ho Kim, Hyun-Seok Kim, Min-Sik Park, Jai-Young Lee, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

Co3O4 has shown acceptable electrochemical properties as the anode material of Li secondary batteries. In detail, its capacity reached about 700 mAh/g, twice as high as graphite, and 93.4% of initial capacity was retained after 100 cycles. EIS (electrochemical impedance spectroscopy) analyses revealed that after the 1st cycle, the insertion or extraction of Li ions in Co3O4 can occur homogeneously and reversibly (randless-like behavior, homogeneous mixture: Co + Li2O (in the state of Li insertion), Co3O4 (in the state of Li extraction)). In fact, the coulombic efficiency of Co …