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Articles 1 - 12 of 12

Full-Text Articles in Physical Sciences and Mathematics

A Seemless Three-Dimensional Carbon Nanotube Graphene Hybrid Material, Yu Zhu, Lei Li, Gilberto Casillas, Zhengzong Sun, Zheng Yan, Gedeng Ruan, Zhiwei Peng, Abdul-Rahman Raji, Carter Kittrell, Robert Hauge, James Tour May 2014

A Seemless Three-Dimensional Carbon Nanotube Graphene Hybrid Material, Yu Zhu, Lei Li, Gilberto Casillas, Zhengzong Sun, Zheng Yan, Gedeng Ruan, Zhiwei Peng, Abdul-Rahman Raji, Carter Kittrell, Robert Hauge, James Tour

Yu Zhu

Graphene and single-walled carbon nanotubes are carbon materials that exhibit excellent electrical conductivities and large specific surface areas. Theoretical work suggested that a covalently bonded graphene/single-walled carbon nanotube hybrid material would extend those properties to three dimensions, and be useful in energy storage and nanoelectronic technologies. Here we disclose a method to bond graphene and single-walled carbon nanotubes seamlessly during the growth stage. The hybrid material exhibits a surface area 42,000m2 g1 with ohmic contact from the vertically aligned single-walled carbon nanotubes to the graphene. Using aberration-corrected scanning transmission electron microscopy, we observed the covalent transformation of sp2 carbon between …


Three-Dimensional-Network Li3v2(Po4) 3/C Composite As High Rate Lithium Ion Battery Cathode Material And Its Compatibility With Ionic Liquid Electrolytes, Jiantie Xu, Shulei Chou, Cuifeng Zhou, Qinfen Gu, Hua-Kun Liu, S X. Dou Mar 2014

Three-Dimensional-Network Li3v2(Po4) 3/C Composite As High Rate Lithium Ion Battery Cathode Material And Its Compatibility With Ionic Liquid Electrolytes, Jiantie Xu, Shulei Chou, Cuifeng Zhou, Qinfen Gu, Hua-Kun Liu, S X. Dou

Shi Xue Dou

A high performance Li3V2(PO4)3 cathode material for lithium ion batteries was synthesized by the microwave-assisted hydrothermal method followed by a post annealing process. The synchrotron X-ray diffraction analysis results confirmed that single-phase Li3V2(PO4)3 with monoclinic structure was obtained. Scanning electron microscope and transmission electron microscope images revealed that the as-prepared Li3V 2(PO4)3 was composed of nanowires and microsized particles. Electrochemical results demonstrated that the Li 3V2(PO4)3 electrode measured at 10 C after 500 cycles can deliver discharge capacities of 85.4 mAh g-1 and 103.4 mAh g-1, with a capacity retention of 99.3% and 95.9%, in the voltage ranges of 3.0-4.3 …


Band Structure, Magnetic, And Transport Properties Of Two Dimensional Compounds Sr2-Xgdxcoo4, Q W Yao, Xiaolin Wang, H Kimura, S X. Dou, Konstantin Konstantinov, Z X. Cheng, F Hong, H Zhao, H Qiu, Kiyoshi Ozawa Mar 2014

Band Structure, Magnetic, And Transport Properties Of Two Dimensional Compounds Sr2-Xgdxcoo4, Q W Yao, Xiaolin Wang, H Kimura, S X. Dou, Konstantin Konstantinov, Z X. Cheng, F Hong, H Zhao, H Qiu, Kiyoshi Ozawa

Shi Xue Dou

The layered perovskite compound Sr2-xGdxCoO 4 has not yet been subjected to detailed study so far. In this report, structures, transport, magnetic properties, and first principle calculations will be reported for the two dimensional compounds Sr 2-xGdxCoO4 (x 0.5, 0.75, 1, 1.25). Rietveld refinement revealed that these compounds are crystallized in K2NiF 4-type structures with space group I4/mmm. It was found that the lattice parameter c decreases as x increases. Through the Curies Weiss fitting of the temperature dependent magnetization, it was found that the Sr 1.25Gd0.75CoO4 sample exhibits a weak ferromagnetic to paramagnetic transition at about 62 K, with …


Three-Dimensional-Network Li3v2(Po4) 3/C Composite As High Rate Lithium Ion Battery Cathode Material And Its Compatibility With Ionic Liquid Electrolytes, Jiantie Xu, Shulei Chou, Cuifeng Zhou, Qinfen Gu, Hua-Kun Liu, S X. Dou Jan 2014

Three-Dimensional-Network Li3v2(Po4) 3/C Composite As High Rate Lithium Ion Battery Cathode Material And Its Compatibility With Ionic Liquid Electrolytes, Jiantie Xu, Shulei Chou, Cuifeng Zhou, Qinfen Gu, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

A high performance Li3V2(PO4)3 cathode material for lithium ion batteries was synthesized by the microwave-assisted hydrothermal method followed by a post annealing process. The synchrotron X-ray diffraction analysis results confirmed that single-phase Li3V2(PO4)3 with monoclinic structure was obtained. Scanning electron microscope and transmission electron microscope images revealed that the as-prepared Li3V 2(PO4)3 was composed of nanowires and microsized particles. Electrochemical results demonstrated that the Li 3V2(PO4)3 electrode measured at 10 C after 500 cycles can deliver discharge capacities of 85.4 mAh g-1 and 103.4 mAh g-1, with a capacity retention of 99.3% and 95.9%, in the voltage ranges of 3.0-4.3 …


Enhanced Sodium-Ion Battery Performance By Structural Phase Transition From Two-Dimensional Hexagonal-Sns2 To Orthorhombic-Sns, Tengfei Zhou, Wei Kong Pang, Chaofeng Zhang, Jianping Yang, Zhixin Chen, Hua-Kun Liu, Zaiping Guo Jan 2014

Enhanced Sodium-Ion Battery Performance By Structural Phase Transition From Two-Dimensional Hexagonal-Sns2 To Orthorhombic-Sns, Tengfei Zhou, Wei Kong Pang, Chaofeng Zhang, Jianping Yang, Zhixin Chen, Hua-Kun Liu, Zaiping Guo

Australian Institute for Innovative Materials - Papers

Structural phase transitions can be used to alter the properties of a material without adding any additional elements and are therefore of significant technological value. It was found that the hexagonal-SnS2 phase can be transformed into the orthorhombic-SnS phase after an annealing step in an argon atmosphere, and the thus transformed SnS shows enhanced sodium-ion storage performance over that of the SnS2, which is attributed to its structural advantages. Here, we provide the first report on a SnS@graphene architecture for application as a sodium-ion battery anode, which is built from two-dimensional SnS and graphene nanosheets as complementary building blocks. The …


Nonlinear Optical Conductivity Of Two-Dimensional Semiconductors With Rashba Spin-Orbit Coupling In Terahertz Regime, Yee Sin Ang, J C. Cao, Chao Zhang Jan 2014

Nonlinear Optical Conductivity Of Two-Dimensional Semiconductors With Rashba Spin-Orbit Coupling In Terahertz Regime, Yee Sin Ang, J C. Cao, Chao Zhang

Australian Institute for Innovative Materials - Papers

We reveal that two-dimensional semiconductors with Rashba spin-orbit interaction (R2DG) exhibit exceptionally strong nonlinear optical response (NOR) in the terahertz frequency regime. The spin-split of the parabolic energy band in R2DG allows strong multiple-photon process to occur via inter-subband mechanism. We show sharp multiple photon edges in the nonlinear conductivity. The edges correspond to the cut-off effect produced by the multiple-photon process. For Rashba coupling parameter of λ R ≈ 10−10 eV m, electric field strength in the order of only 102 V/cm is required for the NOR to dominate over the linear response. Furthermore, the roles of the parabolic …


Three Dimensional (3d) Printed Electrodes For Interdigitated Supercapacitors, Chen Zhao, Caiyun Wang, Robert Gorkin Iii, Stephen Beirne, Kewei Shu, Gordon G. Wallace Jan 2014

Three Dimensional (3d) Printed Electrodes For Interdigitated Supercapacitors, Chen Zhao, Caiyun Wang, Robert Gorkin Iii, Stephen Beirne, Kewei Shu, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Common fabrication techniques typically require multiple and complex MEMS processing steps to create 3D electrode architectures. Here we report on the use of Additive Fabrication metal printing based on Selective Laser Melting (SLM) technology to produce 3D titanium interdigitated electrodes. This was used as a platform to deposit polypyrrole and the resultant structure was evaluated for use as a capacitive electrode. We also demonstrate a solid-state interdigitated supercapacitor using a poly(vinyl alcohol) (PVA)-H3PO4 polymer electrolyte.


Tuning Three-Dimensional Tio2 Nanotube Electrode To Achieve High Utilization Of Ti Substrate For Lithium Storage, Zhijia Zhang, Qing-Yi Zeng, Shulei Chou, Xinjun Li, Huijun Li, Kiyoshi Ozawa, Hua-Kun Liu, Jiazhao Wang Jan 2014

Tuning Three-Dimensional Tio2 Nanotube Electrode To Achieve High Utilization Of Ti Substrate For Lithium Storage, Zhijia Zhang, Qing-Yi Zeng, Shulei Chou, Xinjun Li, Huijun Li, Kiyoshi Ozawa, Hua-Kun Liu, Jiazhao Wang

Australian Institute for Innovative Materials - Papers

Three-dimensional (3D) TiO2 nanotube arrays grown on Ti mesh were prepared via the anodization process. The diameters of the Ti and TiO 2/Ti wires and the length of the TiO2 nanotubes have linear relationships with the anodization processing time. When the anodization processing time is 600 min, the TiO2/Ti mesh anode materials showed good capacity retention and high specific area capacity, without the need for a current collector or binder, due to their high surface area, high substrate utilization, and large active material loading rate per unit area. At the current density of 50 μA cm-2, TiO2/Ti mesh with 600 …


3-Dimensional (3d) Fabricated Polymer Based Drug Delivery Systems, Simon Moulton, Gordon G. Wallace Jan 2014

3-Dimensional (3d) Fabricated Polymer Based Drug Delivery Systems, Simon Moulton, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Drug delivery from 3-dimensional (3D) structures is a rapidly growing area of research. It is essential to achieve structures wherein drug stability is ensured, the drug loading capacity is appropriate and the desired controlled release profile can be attained. Attention must also be paid to the development of appropriate fabrication machinery that allows 3D drug delivery systems (DDS) to be produced in a simple, reliable and reproducible manner. The range of fabrication methods currently being used to form 3D DDSs include electrospinning (solution and melt), wet-spinning and printing (3-dimensional). The use of these techniques enables production of DDSs from the …


Tio2 Coated Three-Dimensional Hierarchically Ordered Porous Sulfur Electrode For The Lithium/Sulfur Rechargeable Batteries, Hongqiang Wang, Sha Li, Dan Li, Zhixin Chen, Hua-Kun Liu, Zaiping Guo Jan 2014

Tio2 Coated Three-Dimensional Hierarchically Ordered Porous Sulfur Electrode For The Lithium/Sulfur Rechargeable Batteries, Hongqiang Wang, Sha Li, Dan Li, Zhixin Chen, Hua-Kun Liu, Zaiping Guo

Australian Institute for Innovative Materials - Papers

A three-dimensional (3D) hierarchically ordered mesoporous carbon-sulfur composite slice coated with a thin TiO2 layer has been synthesized by a low-cost process and investigated as a cathode for the lithium-sulfur batteries. The TiO2 coated carbon sulfur composite thin slice works as a binder-free cathode without any current collectors for lithium-sulfur batteries. The hierarchical architecture provides a 3D conductive network for electron transfer, open channels for ion diffusion and strong confinement of soluble polysulfides. Meanwhile, TiO2 (titanium dioxide) coating layer could further effectively prevent the dissolution of polysulfides and also improve the strength of the entire electrode, thereby enhancing the electrochemical …


Three-Dimensional Printing Fiber Reinforced Hydrogel Composites, Shannon Bakarich, Robert Gorkin Iii, Marc In Het Panhuis, Geoffrey M. Spinks Jan 2014

Three-Dimensional Printing Fiber Reinforced Hydrogel Composites, Shannon Bakarich, Robert Gorkin Iii, Marc In Het Panhuis, Geoffrey M. Spinks

Australian Institute for Innovative Materials - Papers

An additive manufacturing process that combines digital modeling and 3D printing was used to prepare fiber reinforced hydrogels in a single-step process. The composite materials were fabricated by selectively pattering a combination of alginate/acrylamide gel precursor solution and an epoxy based UV-curable adhesive (Emax 904 Gel-SC) with an extrusion printer. UV irradiation was used to cure the two inks into a single composite material. Spatial control of fiber distribution within the digital models allowed for the fabrication of a series of materials with a spectrum of swelling behavior and mechanical properties with physical characteristics ranging from soft and wet to …


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 …