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Mechanically Strong High Performance Layered Polypyrrole Nano Fibre/Graphene Film For Flexible Solid State Supercapacitor, Sha Li, Chen Zhao, Kewei Shu, Caiyun Wang, Zaiping Guo, Gordon G. Wallace, Hua-Kun Liu Jan 2014

Mechanically Strong High Performance Layered Polypyrrole Nano Fibre/Graphene Film For Flexible Solid State Supercapacitor, Sha Li, Chen Zhao, Kewei Shu, Caiyun Wang, Zaiping Guo, Gordon G. Wallace, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Paper like flexible electrode becomes one of the most important research objects recently in request of the fast expanding market of portable electronics. Flexible solid state supercapacitors are shortlisted as one of the most promising energy devices to power electronics with medium to high power density requirements. In this work, we developed a simple but effective way to produce a mechanically strong and electrochemically active RGO/polypyrrole (PPy) fibre paper. A well-bedded microstructure was created with interlaced polypyrrole fibres evenly distributed between the graphene layers. Such microstructure can create enormous amount of pores and therefore provides larger interfaces for charge carrier …


Electronic Coupling And Catalytic Effect On H2 Evolution Of Mos2/Graphene Nanocatalyst, Ting Liao, Ziqi Sun, Chenghua Sun, S X. Dou, Debra J. Searles Jan 2014

Electronic Coupling And Catalytic Effect On H2 Evolution Of Mos2/Graphene Nanocatalyst, Ting Liao, Ziqi Sun, Chenghua Sun, S X. Dou, Debra J. Searles

Australian Institute for Innovative Materials - Papers

Inorganic nano-graphene hybrid materials that are strongly coupled via chemical bonding usually present superior electrochemical performance. However, how the chemical bond forms and the synergistic catalytic mechanism remain fundamental questions. In this study, the chemical bonding of the MoS 2 nanolayer supported on vacancy mediated graphene and the hydrogen evolution reaction of this nanocatalyst system were investigated. An obvious reduction of the metallic state of the MoS 2 nanolayer is noticed as electrons are transferred to form a strong contact with the reduced graphene support. The missing metallic state associated with the unsaturated atoms at the peripheral sites in turn …


Interplay Between Boron Precursors And Ni-Co-B Nanoparticle Doping In The Fabrication Of Mgb2 Superconductor With Improved Electromagnetic Properties, Mislav Mustapic, Josip Horvat, Zeljko Skoko, Md Shahriar Hossain, S X. Dou Jan 2014

Interplay Between Boron Precursors And Ni-Co-B Nanoparticle Doping In The Fabrication Of Mgb2 Superconductor With Improved Electromagnetic Properties, Mislav Mustapic, Josip Horvat, Zeljko Skoko, Md Shahriar Hossain, S X. Dou

Australian Institute for Innovative Materials - Papers

The influence of different boron precursor powders on the critical current density of MgB2 superconductor with added Ni-Co-B nanoparticles is investigated. Different types of boron have different morphologies, particle sizes and impurity content, all of which have a strong impact on the critical current density (Jc). The boron samples investigated in this study include three different boron powders: semicrystalline boron (denoted as SC), with nanosized particles and high purity (99%) supplied from Specialty Materials, Inc. (USA); amorphous boron (denoted as AB), with nanosized particles and high purity (99%) supplied from Russia; and finally pure crystalline boron (denoted as CB), with …


Facile Synthesis Of Highly Efficient One-Dimensional Plasmonic Photocatalysts Through Ag@Cu2o Core-Shell Heteronanowires, Jinyan Xiong, Zhen Li, Jun Chen, Shanqing Zhang, Lianzhou Wang, S X. Dou Jan 2014

Facile Synthesis Of Highly Efficient One-Dimensional Plasmonic Photocatalysts Through Ag@Cu2o Core-Shell Heteronanowires, Jinyan Xiong, Zhen Li, Jun Chen, Shanqing Zhang, Lianzhou Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

A novel class of one-dimensional (1D) plasmonic Ag@Cu2O core-shell heteronanowires have been synthesized at room temperature for photocatalysis application. The morphology, size, crystal structure and composition of the products were investigated by XRD, SEM, TEM, XPS, and UV-vis instruments. It was found the reaction time and the amount of Ag nanowires play crucial roles in the formation of well-defined 1D Ag@Gu(2)O core-shell heteronanowires. The resultant 1D Ag@Cu2O NWs exhibit much higher photocatalytic activity toward degradation of organic contaminants than Ag@Cu2O core-shell nanopartides or pure Cu2O nanospheres under solar light irradiation. The drastic enhancement in photocatalytic activity could be attributed to …


Sulfur-Graphene Nanostructured Cathodes Via Ball-Milling For High-Performance Lithium-Sulfur Batteries, Jiantie Xu, Jianglan Shui, Jianli Wang, Min Wang, Hua-Kun Liu, S X. Dou, In-Yup Jeon, Jeong-Min Seo, Jong-Beom Baek, Liming Dai Jan 2014

Sulfur-Graphene Nanostructured Cathodes Via Ball-Milling For High-Performance Lithium-Sulfur Batteries, Jiantie Xu, Jianglan Shui, Jianli Wang, Min Wang, Hua-Kun Liu, S X. Dou, In-Yup Jeon, Jeong-Min Seo, Jong-Beom Baek, Liming Dai

Australian Institute for Innovative Materials - Papers

Although much progress has been made to develop high-performance lithium-sulfur batteries (LSBs), the reported physical or chemical routes to sulfur cathode materials are often multistep/complex and even involve environmentally hazardous reagents, and hence are infeasible for mass production. Here, we report a simple ball-milling technique to combine both the physical and chemical routes into a one-step process for low-cost, scalable, and eco-friendly production of graphene nanoplatelets (GnPs) edge-functionalized with sulfur (S-GnPs) as highly efficient LSB cathode materials of practical significance. LSBs based on the S-GnP cathode materials, produced by ball-milling 70 wt % sulfur and 30 wt % graphite, delivered …


In-Situ One-Step Hydrothermal Synthesis Of A Lead Germanate-Graphene Composite As A Novel Anode Material For Lithium-Ion Batteries, Jun Wang, Chuan-Qi Feng, Ziqi Sun, Shulei Chou, Hua-Kun Liu, Jia-Zhao Wang Jan 2014

In-Situ One-Step Hydrothermal Synthesis Of A Lead Germanate-Graphene Composite As A Novel Anode Material For Lithium-Ion Batteries, Jun Wang, Chuan-Qi Feng, Ziqi Sun, Shulei Chou, Hua-Kun Liu, Jia-Zhao Wang

Australian Institute for Innovative Materials - Papers

Lead germanate-graphene nanosheets (PbGeO3-GNS) composites have been prepared by an efficient one-step, in-situ hydrothermal method and were used as anode materials for Li-ion batteries (LIBs). The PbGeO3 nanowires, around 100-200 nm in diameter, are highly encapsulated in a graphene matrix. The lithiation and de-lithiation reaction mechanisms of the PbGeO3 anode during the charge-discharge processes have been investigated by X-ray diffraction and electrochemical characterization. Compared with pure PbGeO3 anode, dramatic improvements in the electrochemical performance of the composite anodes have been obtained. In the voltage window of 0.01-1.50 V, the composite anode with 20 wt.% GNS delivers a discharge capacity of …


Ambient Scalable Synthesis Of Surfactant-Free Thermoelectric Cuagse Nanoparticles With Reversible Metallic-N-P Conductivity Transition, Chao Han, Qiao Sun, Zhenxiang Cheng, Jianli Wang, Zhen Li, Gao Qing (Max) Lu, S X. Dou Jan 2014

Ambient Scalable Synthesis Of Surfactant-Free Thermoelectric Cuagse Nanoparticles With Reversible Metallic-N-P Conductivity Transition, Chao Han, Qiao Sun, Zhenxiang Cheng, Jianli Wang, Zhen Li, Gao Qing (Max) Lu, S X. Dou

Australian Institute for Innovative Materials - Papers

Surfactant-free CuAgSe nanoparticles were successfully synthesized on a large scale within a short reaction time via a simple environmentally friendly aqueous approach under room temperature. The nanopowders obtained were consolidated into pellets for investigation of their thermoelectric properties between 3 and 623 K. The pellets show strong metallic characteristics below 60 K and turn into an n-type semiconductor with increasing temperature, accompanied by changes in the crystal structure (i.e., from the pure tetragonal phase into a mixture of tetragonal and orthorhombic phases), the electrical conductivity, the Seebeck coefficient, and the thermal conductivity, which leads to a figure of merit (ZT) …


Enhancing The High Rate Capability And Cycling Stability Of Limn2o4 By Coating Of Solid-State Electrolyte Linbo3, Zhijia Zhang, Shulei Chou, Qinfen Gu, Hua-Kun Liu, Huijun Li, Kiyoshi Ozawa, Jiazhao Wang Jan 2014

Enhancing The High Rate Capability And Cycling Stability Of Limn2o4 By Coating Of Solid-State Electrolyte Linbo3, Zhijia Zhang, Shulei Chou, Qinfen Gu, Hua-Kun Liu, Huijun Li, Kiyoshi Ozawa, Jiazhao Wang

Australian Institute for Innovative Materials - Papers

To study the influence of solid state electrolyte coating layers on the performance of cathode materials for lithium-ion batteries in combination with organic liquid electrolyte, LiNbO3 coated Li1.08Mn1.92O4 cathode materials were synthesized by using a facile solid-state reaction method. The 0.06LiNbO3-0.97Li1.08Mn1.92O4 cathode exhibited an initial discharge capacity of 125 mAh g-1, retaining a capacity of 119 mAh g-1, at 25 oC, while at 55 oC, it exhibited an initial discharge capacity of 130 mAh g-1, retaining a capacity of 111 mAh g-1, both at a current density of 0.5 C (where 1 C is 148 mAh g-1). Very good rate …


One-Step Synthesis Of Graphene/Polypyrrole Nanofiber Composites As Cathode Material For A Biocompatible Zinc/Polymer Battery, Sha Li, Kewei Shu, Chen Zhao, Caiyun Wang, Zaiping Guo, Gordon G. Wallace, Hua-Kun Liu Jan 2014

One-Step Synthesis Of Graphene/Polypyrrole Nanofiber Composites As Cathode Material For A Biocompatible Zinc/Polymer Battery, Sha Li, Kewei Shu, Chen Zhao, Caiyun Wang, Zaiping Guo, Gordon G. Wallace, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

The significance of developing implantable, biocompatible, miniature power sources operated in a low current range has become manifest in recent years to meet the demands of the fast-growing market for biomedical microdevices. In this work, we focus on developing high-performance cathode material for biocompatible zinc/polymer batteries utilizing biofluids as electrolyte. Conductive polymers and graphene are generally considered to be biocompatible and suitable for bioengineering applications. To harness the high electrical conductivity of graphene and the redox capability of polypyrrole (PPy), a polypyrrole fiber/graphene composite has been synthesized via a simple one-step route. This composite is highly conductive (141 S cm …


A Method For Systematic Electrochemical And Electrophysiological Evaluation Of Neural Recording Electrodes, Alexander R. Harris, Simeon J. Morgan, Gordon G. Wallace, Antonio Paolini Jan 2014

A Method For Systematic Electrochemical And Electrophysiological Evaluation Of Neural Recording Electrodes, Alexander R. Harris, Simeon J. Morgan, Gordon G. Wallace, Antonio Paolini

Australian Institute for Innovative Materials - Papers

New materials and designs for neural implants are typically tested separately, with a demonstration of performance but without reference to other implant characteristics. This precludes a rational selection of a particular implant as optimal for a particular application and the development of new materials based on the most critical performance parameters. This article develops a protocol for in vitro and in vivo testing of neural recording electrodes. Recommended parameters for electrochemical and electrophysiological testing are documented with the key steps and potential issues discussed. This method eliminates or reduces the impact of many systematic errors present in simpler in vivo …


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 …


Magnetic Properties And Magnetocaloric Effect In Layered Ndmn1.9ti0.1si2, M F. Md Din, Jianli Wang, Shane J. Kennedy, Stewart J. Campbell, S X. Dou Jan 2014

Magnetic Properties And Magnetocaloric Effect In Layered Ndmn1.9ti0.1si2, M F. Md Din, Jianli Wang, Shane J. Kennedy, Stewart J. Campbell, S X. Dou

Australian Institute for Innovative Materials - Papers

The structural and magnetic properties of the NdMn1.9Ti0.1Si2 compund have been studied by high-intensity x-ray and high-resolution neutron powder diffraction, specific heat, dc magnetization, and differential scanning calorimetry measurements over the temperature range of 3-450 K. The Curie temperature and Néel temperature of layered NdMn1.9Ti0.1Si2 are indicated as TC ~ 22 K and TN ~ 374 K respectively. The first order magnetic transition from antiferromagnetic [AFil-type] to ferromagnetic [F(Nd)+Fmc] around TC is found in layered NdMn1.9Ti0.1Si2 and is …


Photoelectrochemical Reduction Of Aqueous Protons With A Cuo|Cubi2o4 Heterojunction Under Visible Light Irradiation, Hyun S. Park, Chong-Yong Lee, Erwin Reisner Jan 2014

Photoelectrochemical Reduction Of Aqueous Protons With A Cuo|Cubi2o4 Heterojunction Under Visible Light Irradiation, Hyun S. Park, Chong-Yong Lee, Erwin Reisner

Australian Institute for Innovative Materials - Papers

A p-type heterojunction photoelectrode consisting of platinized CuBi2O4 layered on a CuO film was prepared. The CuO|CuBi2O4|Pt electrode photo-generates H2 in pH neutral aqueous solution during visible light irradiation and exhibits a substantially enhanced photocurrent compared to CuO|Pt and CuBi2O4|Pt electrodes. Reduced electron-hole recombination by the band offsets in the heterostructure is responsible for the improved photoelectrochemical performance of CuO|CuBi2O4 with a small band-gap of approximately 1.5 eV.


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 …


One-Pot Synthesis Of Α-Fe2o3 Nanoparticles-Decorated Reduced Graphene Oxide For Efficient Nonenzymatic H2o2 Biosensor, Ming-Yan Wang, Tao Shen, Meng Wang, Dong-En Zhang, Zhi-Wei Tong, Jun Chen Jan 2014

One-Pot Synthesis Of Α-Fe2o3 Nanoparticles-Decorated Reduced Graphene Oxide For Efficient Nonenzymatic H2o2 Biosensor, Ming-Yan Wang, Tao Shen, Meng Wang, Dong-En Zhang, Zhi-Wei Tong, Jun Chen

Australian Institute for Innovative Materials - Papers

Hematite nanoparticles (α-Fe2O3) are successfully decorated on the reduced graphene oxide (rGO) sheets through a simple, one-step, hydrothermal method without addition of other reducing agents. The α-Fe2O3/rGO hybrid was characterized by scanning electron micrographs, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy. This α-Fe2O3/rGO hybrid has been successfully applied in the catalytic performance toward the reduction of H2O2. The nonenzymatic sensor demonstrates a linear relationship over a wide concentration range of 5.0–4495.0 μM (R = 0.9998), a low detection limit of 1.0 μM, and a high sensitivity of 126.9 μA cm−2 mM−1 to the detection of H2O2.


Spin Memristive Magnetic Tunnel Junctions With Coo-Zno Nano Composite Barrier, Qiang Li, Ting-Ting Shen, Yan-Ling Cao, Kun Zhang, Shi-Shen Yan, Yu-Feng Tian, Shi-Shou Kang, Ming-Wen Zhao, You-Yong Dai, Yan-Xue Chen, Guo-Lei Liu, Liang-Mo Mei, Xiaolin Wang, Peter Grunberg Jan 2014

Spin Memristive Magnetic Tunnel Junctions With Coo-Zno Nano Composite Barrier, Qiang Li, Ting-Ting Shen, Yan-Ling Cao, Kun Zhang, Shi-Shen Yan, Yu-Feng Tian, Shi-Shou Kang, Ming-Wen Zhao, You-Yong Dai, Yan-Xue Chen, Guo-Lei Liu, Liang-Mo Mei, Xiaolin Wang, Peter Grunberg

Australian Institute for Innovative Materials - Papers

The spin memristive devices combining memristance and tunneling magnetoresistance have promising applications in multibit nonvolatile data storage and artificial neuronal computing. However, it is a great challenge for simultaneous realization of large memristance and magnetoresistance in one nanoscale junction, because it is very hard to find a proper spacer layer which not only serves as good insulating layer for tunneling magnetoresistance but also easily switches between high and low resistance states under electrical field. Here we firstly propose to use nanon composite barrier layers of CoO-ZnO to fabricate the spin memristive Co/CoO-ZnO/Co magnetic tunnel junctions. The bipolar resistance switching ratio …


Magnetic Phase Transitions And Entropy Change In Layered Ndmn1.7cr0.3si2, M F. Md Din, Jianli Wang, S J. Campbell, A J. Studer, M Avdeev, S J. Kennedy, Q F. Gu, R Zeng, S X. Dou Jan 2014

Magnetic Phase Transitions And Entropy Change In Layered Ndmn1.7cr0.3si2, M F. Md Din, Jianli Wang, S J. Campbell, A J. Studer, M Avdeev, S J. Kennedy, Q F. Gu, R Zeng, S X. Dou

Australian Institute for Innovative Materials - Papers

A giant magnetocaloric effect has been observed around the Curie temperature, TC ∼ 42 K, in NdMn1.7Cr0.3Si2 with no discernible thermal and magnetic hysteresis losses. Below 400 K, three magnetic phase transitions take place around 380 K, 320 K and 42 K. Detailed high resolution synchrotron and neutron powder diffraction (10-400 K) confirmed the magnetic transitions and phases as follows: TN intra ∼ 380 K denotes the transition from paramagnetism to intralayer antiferromagnetism (AFl), TN inter ∼ 320 K represents the transition from the AFl structure to the canted antiferromagnetic spin structure (AFmc), while TC ∼ 42 K denotes the …


Optimization Of The Sequential Polymerization Synthesis Method For Polypyrrole Films, Danial Sangian, Wen Zheng, Geoffrey M. Spinks Jan 2014

Optimization Of The Sequential Polymerization Synthesis Method For Polypyrrole Films, Danial Sangian, Wen Zheng, Geoffrey M. Spinks

Australian Institute for Innovative Materials - Papers

Polypyrrole (PPy) is widely used as an electroactive material and is most often synthesized using electrochemical polymerization. Recently, a new electropolymerization method [1] was introduced that involved preparing the PPy as a sequential series of electrodeposited layers with solvent washing in between each deposited layer. This method enabled high quality PPy free-standing films to be prepared in a relatively short time. The purpose of the present study was to investigate the effect of the polymerization current density on the mechanical and electrical properties of the sequentially polymerized (SEP) PPy films. It was found that a low current density (0.1 mA/cm2) …


Temperature Dependent Photoexcited Carrier Dynamics In Multiferroic Bifeo3 Film: A Hidden Phase Transition, Zeyu Zhang, Zuanming Jin, Qunfeng Pan, Yue Xu, Xian Lin, Guohong Ma, Zhenxiang Cheng Jan 2014

Temperature Dependent Photoexcited Carrier Dynamics In Multiferroic Bifeo3 Film: A Hidden Phase Transition, Zeyu Zhang, Zuanming Jin, Qunfeng Pan, Yue Xu, Xian Lin, Guohong Ma, Zhenxiang Cheng

Australian Institute for Innovative Materials - Papers

The ultrafast carrier dynamics of the multiferroic BiFeO3 film in a broad temperature range is investigated using optical pump-probe spectroscopy. The photoexcited electrons release their energy with optical phonons emission through electron-phonon coupling in about 1 ps. The following intermediate process is identified as dynamical spin-lattice coupling in several picoseconds. Furthermore, the peak values of the optical reflectivity and the time constants of carrier relaxation channels show significant changes while the temperature varies from 137.5 K to around 195 K, this aligns with the previously reported hidden phase transition. Our study demonstrates that ultrafast spectroscopy is a sensitive method to …