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Articles 1171 - 1200 of 4868

Full-Text Articles in Physical Sciences and Mathematics

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 …

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Tuning The Band Gap In Silicene By Oxidation, Yi Du, Jincheng Zhuang, Hongsheng Liu, Xun Xu, Stefan Eilers, Kehui Wu, Peng Cheng, Jijun Zhao, Xiaodong Pi, Khay Wai See, Germanas Peleckis, Xiaolin Wang, S X. Dou Jan 2014

Tuning The Band Gap In Silicene By Oxidation, Yi Du, Jincheng Zhuang, Hongsheng Liu, Xun Xu, Stefan Eilers, Kehui Wu, Peng Cheng, Jijun Zhao, Xiaodong Pi, Khay Wai See, Germanas Peleckis, Xiaolin Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

Silicene monolayers grown on Ag(111) surfaces demonstrate a band gap that is tunable by oxygen adatoms from semimetallic to semiconducting type. With the use of low-temperature scanning tunneling microscopy, we find that the adsorption configurations and amounts of oxygen adatoms on the silicene surface are critical for band gap engineering, which is dominated by different buckled structures in √13 x √13, 4 x 4, and 2√3 x 2√3 silicene layers. The Si-O-Si bonds are the most energy-favored species formed on √13 x √13, 4 x 4, and 2√3 x 2√3 structures under oxidation, which is verified by in situ Raman …

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A Novel Codoping Approach For Enhancing The Performance Of Polypyrrole Cathode In A Bioelectric Battery, Yang Yang, Caiyun Wang, Chunming Zhang, Dan Wang, Dannong He, Gordon G. Wallace Jan 2014

A Novel Codoping Approach For Enhancing The Performance Of Polypyrrole Cathode In A Bioelectric Battery, Yang Yang, Caiyun Wang, Chunming Zhang, Dan Wang, Dannong He, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

A conducting polymer (CP) based bioelectric battery provides a promising alternative to commercial lithium batteries to drive biomedical devices. However, the low power density limits practical application. Here, we synthesize a polypyrrole (PPy)/anthraquinone sulfonate (AQS)/reduced graphene oxide (r-GO) composite via a facile electrochemical route, and use this as a novel cathode material for bioelectric batteries. The presence of r-GO significantly enhanced the electrochemical properties of PPy and led to greatly improved cell performance compared to that of PPy/AQS. The resultant PPy/AQS/r-GO composite delivered a maximum power density of 6240.5 mW m(-2), 14.2 times higher than that of PPy/p-toluenesulfonate (pTS) as …

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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 …

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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 …

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Pb Thin Films On Si(111): Local Density Of States And Defects, Stefan Eilers, Yi Du, S X. Dou Jan 2014

Pb Thin Films On Si(111): Local Density Of States And Defects, Stefan Eilers, Yi Du, S X. Dou

Australian Institute for Innovative Materials - Papers

Local density of states and atomic structure of the stripped incommensurate phase, the √3 x√7 phase and the 1 x 1 phase of a monolayer of Pb on Si(111) are characterized by scanning tunneling microscopy and spectroscopy. The dI/dV-images reveal congruent local density of states structures for the stripped incommensurate and the √3 x√ phase but suggest a hexagonal lattice of the local density of states for the 1x1 phase while the atomic structure consists of one more atom in the center of each hexagon. Vacancy defects and impurities show a depletion of local density of states for the stripped …

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Biocompatible Ionic Liquid-Biopolymer Electrolyte Enabled Thin And Compact Magnesium Air Batteries, Xiaoteng Jia, Yang Yang, Caiyun Wang, Chen Zhao, R Vijayaraghavan, Douglas R. Macfarlane, Maria Forsyth, Gordon G. Wallace Jan 2014

Biocompatible Ionic Liquid-Biopolymer Electrolyte Enabled Thin And Compact Magnesium Air Batteries, Xiaoteng Jia, Yang Yang, Caiyun Wang, Chen Zhao, R Vijayaraghavan, Douglas R. Macfarlane, Maria Forsyth, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

With the surge of interest in miniaturized implanted medical devices (IMDs), implantable power sources with small dimensions and biocompatibility are in high demand. Implanted battery/supercapacitor devices are commonly packaged within a case that occupies a large volume, making miniaturization difficult. In this study, we demonstrate a polymer electrolyte-enabled biocompatible magnesium-air battery device with a total thickness of approximately 300 μm. It consists of a biocompatible polypyrrole-para(toluene sulfonic acid) cathode and a bioresorbable magnesium alloy anode. The biocompatible electrolyte used is made of choline nitrate (ionic liquid) embedded in a biopolymer, chitosan. This polymer electrolyte is mechanically robust and offers a …

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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 …

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A Dye-Sensitized Visible Light Photocatalyst-Bi24o31cl10, Liang Wang, Jun Shang, Weichang Hao, Shiqi Jiang, Shiheng Huang, Tianmin Wang, Ziqi Sun, Yi Du, S X. Dou, Tengfeng Xie, Dejun Wang, Jiaou Wang Jan 2014

A Dye-Sensitized Visible Light Photocatalyst-Bi24o31cl10, Liang Wang, Jun Shang, Weichang Hao, Shiqi Jiang, Shiheng Huang, Tianmin Wang, Ziqi Sun, Yi Du, S X. Dou, Tengfeng Xie, Dejun Wang, Jiaou Wang

Australian Institute for Innovative Materials - Papers

The p-block semiconductors are regarded as a new family of visible-light photocatalysts because of their dispersive and anisotropic band structures as well as high chemical stability. The bismuth oxide halides belong to this family and have band structures and dispersion relations that can be engineered by modulating the stoichiometry of the halogen elements. Herein, we have developed a new visible-light photocatalyst Bi24O31Cl10 by band engineering, which shows high dye-sensitized photocatalytic activity. Density functional theory calculations reveal that the p-block elements determine the nature of the dispersive electronic structures and narrow band gap in Bi24O31Cl10. Bi24O31Cl10 exhibits excellent visible-light photocatalytic activity …

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Effects Of Oxygen Adsorption On The Surface State Of Epitaxial Silicene On Ag(111), Xun Xu, Jincheng Zhuang, Yi Du, Haifeng Feng, N Zhang, Chen Liu, Tao Lei, Jiaou Wang, M Spencer, Tetsuya Morishita, Xiaolin Wang, S X. Dou Jan 2014

Effects Of Oxygen Adsorption On The Surface State Of Epitaxial Silicene On Ag(111), Xun Xu, Jincheng Zhuang, Yi Du, Haifeng Feng, N Zhang, Chen Liu, Tao Lei, Jiaou Wang, M Spencer, Tetsuya Morishita, Xiaolin Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

Epitaxial silicene, which is one single layer of silicon atoms packed in a honeycomb structure, demonstrates a strong interaction with the substrate that dramatically affects its electronic structure. The role of electronic coupling in the chemical reactivity between the silicene and the substrate is still unclear so far, which is of great importance for functionalization of silicene layers. Here, we report the reconstructions and hybridized electronic structures of epitaxial 4 3 4 silicene on Ag(111), which are revealed by scanning tunneling microscopy and angle-resolved photoemission spectroscopy. The hybridization between Si and Ag results in a metallic surface state, which can …

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The Formation Of Nano-Layered Grains And Their Enhanced Superconducting Transition Temperature In Mg-Doped Fese0.9 Bulks, Feng Lan, Zongqing Ma, Yongchang Liu, Ning Chen, Qi Cai, Huijun Li, Shaon Barua, Dipakkumar Patel, Md Shahriar Hossain, Jung Ho Kim, S X. Dou Jan 2014

The Formation Of Nano-Layered Grains And Their Enhanced Superconducting Transition Temperature In Mg-Doped Fese0.9 Bulks, Feng Lan, Zongqing Ma, Yongchang Liu, Ning Chen, Qi Cai, Huijun Li, Shaon Barua, Dipakkumar Patel, Md Shahriar Hossain, Jung Ho Kim, S X. Dou

Australian Institute for Innovative Materials - Papers

To search a proper dopant to further improve superconductivity in 11 type Fe-based superconductors makes sense to both their superconductivity mechanism and possible technological applications. In present work, Mg doped FeSe polycrystalline bulks were obtained by a two-step solid-state reaction method. Even though there are many MgSe and iron impurities existing in the Mg heavy doped FeSe bulks, they exhibit obviously increased Tc compared to undoped FeSe sample. It was found that Mg addition has little effect on the crystal lattice parameters of superconducting beta-FeSe, whereas leads to the formation of nano-layered grain structure consisted of MgSe and beta-FeSe …

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A Triblock-Copolymer-Templating Route To Carbon Spheres@Sba-15 Large Mesopore Core-Shell And Hollow Structures, Jianping Yang, Xianghong Qian, Minjun Chen, Jianwei Fan, Hua-Kun Liu, Weixian Zhang Jan 2014

A Triblock-Copolymer-Templating Route To Carbon Spheres@Sba-15 Large Mesopore Core-Shell And Hollow Structures, Jianping Yang, Xianghong Qian, Minjun Chen, Jianwei Fan, Hua-Kun Liu, Weixian Zhang

Australian Institute for Innovative Materials - Papers

The fabrication of mesoporous core-shell and hollow spheres with ordered mesostructures and tunable large pore sizes is highly desirable for fundamental research and practical applications. A direct triblock-copolymer-templating coating approach has been provided for the synthesis of carbon sphere@mesoporous silica core-shell (CS@SBA-15) and hollow structures in an acidic medium at room temperature. These CS@SBA-15 core-shell structures possess large mesopores (6.3-8.4 nm), high surface areas (318.1-438.4 m2 g-1) and large pore volumes (0.31-0.36 cm3 g-1). The corresponding hollow mesoporous silica spheres (HMSS) with controllable mesopores (6.0-8.2 nm), high surface areas (239.9-326.5 m2 g-1 …

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Electrically Contractile Polymers Augment Right Ventricular Output In The Heart, Arjang Ruhparwar, Patricia Piontek, Matthias Ungerer, Ali Ghodsizad, Sasan Partovi, Javad Foroughi, Gabor Szabo, Mina Farag, Matthias Karck, Geoffrey M. Spinks, Seon Jeong Kim Jan 2014

Electrically Contractile Polymers Augment Right Ventricular Output In The Heart, Arjang Ruhparwar, Patricia Piontek, Matthias Ungerer, Ali Ghodsizad, Sasan Partovi, Javad Foroughi, Gabor Szabo, Mina Farag, Matthias Karck, Geoffrey M. Spinks, Seon Jeong Kim

Australian Institute for Innovative Materials - Papers

Research into the development of artificial heart muscle has been limited to assembly of stem cell-derived cardiomyocytes seeded around a matrix, while nonbiological approaches to tissue engineering have rarely been explored. The aim of the study was to apply electrically contractile polymer-based actuators as cardiomyoplasty for positive inotropic support of the right ventricle. Complex trilayer polypyrrole (PPy) bending polymers for high-speed applications were generated. Bending motion occurred directly as a result of electrochemically driven charging and discharging of the PPy layers. In a rat model (n=5), strips of polymers (3x20mm) were attached and wrapped around the right ventricle …

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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 …

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Non-Wettable, Oxidation-Stable, Brightly Luminescent, Perfluorodecyl-Capped Silicon Nanocrystal Film, Chenxi Qian, Wei Sun, Liwei Wang, Chanlong Chen, Kristine Liao, Wendong Wang, Jia Jia, Benjamin D. Hatton, Gilberto Casillas, Marty Kurylowicz, Christopher M. Yip, Melanie L. Mastronardi, Geoffrey A. Ozin Jan 2014

Non-Wettable, Oxidation-Stable, Brightly Luminescent, Perfluorodecyl-Capped Silicon Nanocrystal Film, Chenxi Qian, Wei Sun, Liwei Wang, Chanlong Chen, Kristine Liao, Wendong Wang, Jia Jia, Benjamin D. Hatton, Gilberto Casillas, Marty Kurylowicz, Christopher M. Yip, Melanie L. Mastronardi, Geoffrey A. Ozin

Australian Institute for Innovative Materials - Papers

Here we describe for the first time the synthesis of colloidally stable, brightly luminescent perfluorodecyl-capped silicon nanocrystals and compare the properties of solutions and films made from them with those of their perhydrodecyl-capped relatives. The perfluorodecyl capping group compared to the perhydrodecyl capping group yields superior hydrophobicity and much greater resistance to air oxidation, the enhanced electron-withdrawing character induces blue shifts in the wavelength of photoluminescence, and the lower-frequency carbon-fluorine stretching modes disfavor non-radiative relaxation pathways and boost the absolute photoluminescence quantum yield. Together these attributes bode well for advanced materials and biomedical applications founded upon perfluorodecyl-protected silicon nanocrystals.

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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 …

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Single Crystalline Co3o4 Nanocrystals Exposed With Different Crystal Planes For Li-O2 Batteries, Dawei Su, S X. Dou, Guoxiu Wang Jan 2014

Single Crystalline Co3o4 Nanocrystals Exposed With Different Crystal Planes For Li-O2 Batteries, Dawei Su, S X. Dou, Guoxiu Wang

Australian Institute for Innovative Materials - Papers

Single crystalline Co3O4 nanocrystals exposed with different crystal planes were synthesised, including cubic Co3O4 nanocrystals enclosed by {100} crystal planes, pseudo octahedral Co3O4 enclosed by {100} and {110} crystal planes, Co3O4 nanosheets exposed by {110} crystal planes, hexagonal Co3O4 nanoplatelets exposed with {111} crystal planes, and Co3O4 nanolaminar exposed with {112} crystal planes. Well single crystalline features of these Co3O4 nanocrystals were confirmed by FESEM and HRTEM analyses. The electrochemical performance for Li-O2 batteries shows that Co3 …

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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 …

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Integrating A Triplet-Triplet Annihilation Up-Conversion System To Enhance Dye-Sensitized Solar Cell Response To Sub-Bandgap Light, Andrew Nattestad, Yuen Yap Cheng, R Macqueen, Gordon G. Wallace, Timothy Schmidt Jan 2014

Integrating A Triplet-Triplet Annihilation Up-Conversion System To Enhance Dye-Sensitized Solar Cell Response To Sub-Bandgap Light, Andrew Nattestad, Yuen Yap Cheng, R Macqueen, Gordon G. Wallace, Timothy Schmidt

Australian Institute for Innovative Materials - Papers

The poor response of dye-sensitized solar cells (DSCs) to red and infrared light is a significant impediment to the realization of higher photocurrents and hence higher efficiencies. Photon up-conversion by way of triplet-triplet annihilation (TTA-UC) is an attractive technique for using these otherwise wasted low energy photons to produce photocurrent, while not interfering with the photoanodic performance in a deleterious manner. Further to this, TTA-UC has a number of features, distinct from other reported photon up-conversion technologies, which renders it particularly suitable for coupling with DSC technology. In this work, a proven high performance TTA-UC system, comprising a palladium porphyrin …

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Recent Progress On Synthesis, Multi-Scale Structure, And Properties Of Y-Si-O Oxides, Ziqi Sun, M S. Li, Y C. Zhou Jan 2014

Recent Progress On Synthesis, Multi-Scale Structure, And Properties Of Y-Si-O Oxides, Ziqi Sun, M S. Li, Y C. Zhou

Australian Institute for Innovative Materials - Papers

Yttrium silicates (Y-Si-O oxides), including Y2Si2O7, Y2SiO5, and Y4·67(SiO4)3O apatite, have attracted wide attentions from material scientists and engineers, because of their extensive polymorphisms and important roles as grain boundary phases in improving the high-temperature mechanical/thermal properties of Si3N4 and SiC ceramics. Recent interest in these materials has been renewed by their potential applications as high-temperature structural ceramics, oxidation protective coatings, and environmental barrier coatings (EBCs). The salient properties of Y-Si-O oxides are strongly related to their unique chemical bonds and …

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Impacts Of Crystal Orientation Of Gaas On The Interfacial Structures And Electrical Properties Of Hf0.6la0.4ox Films, Tingting Jia, Hideo Kimura, Hongyang Zhao, Qiwen Yao, Zhenxiang Cheng, Xinghong Cheng, Yuehui Yu Jan 2014

Impacts Of Crystal Orientation Of Gaas On The Interfacial Structures And Electrical Properties Of Hf0.6la0.4ox Films, Tingting Jia, Hideo Kimura, Hongyang Zhao, Qiwen Yao, Zhenxiang Cheng, Xinghong Cheng, Yuehui Yu

Australian Institute for Innovative Materials - Papers

One of the major challenges in realizing the GaAs channel in the metal oxide semiconductor field effect transistor is the degrading in electron transport properties at the interface between GaAs and the gate oxide. In this study, Hf0.6La0.4Ox gate oxide films were deposited at a low temperature (200 °C) on GaAs(111)A and GaAs(100) substrates by plasma enhanced atomic layer deposition. Microstructure analysis indicates that residuals of gallium oxide, arsenic oxide, and As element remained at the interface of Hf0.6La0.4Ox/GaAs(100). On contrast, a smoother interface is observed between Hf0.6 …

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Conductivity And Oxygen Reduction Activity Changes In Lanthanum Strontium Manganite Upon Low-Level Chromium Substitution, George Tsekouras, Artur Braun Jan 2014

Conductivity And Oxygen Reduction Activity Changes In Lanthanum Strontium Manganite Upon Low-Level Chromium Substitution, George Tsekouras, Artur Braun

Australian Institute for Innovative Materials - Papers

On the timescale of solid oxide fuel cell (SOFC) system lifetime requirements, the thermodynamically predicted low-level substitution of chromium on the B-site of (La,Sr)MnO3 could be a source of cathode degradation underlying more overt and well-known chromium poisoning mechanisms. To study this phenomenon in isolation, electronic conductivity (σ) and electrochemical oxygen reduction activity of the (La0.8Sr0.2)0.98CrxMn1−xO3 model series (x = 0, 0.02, 0.05 or 0.1) were measured in air between 850 and 650 °C. Depending on the extent of chromium substitution and the measurement temperature, electrochemical …

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Degradation Of The Remanent Ferromagnetic State Under The Action Of Ferroelectric Relaxation Processes In Co/(1-X)Pmn-Xpt/Co Hybrids: Possible Implications On Cryogenic And Room-Temperature Applications, Dimosthenis Stamopoulos, M Zeibekis, G Vertsioti, Shujun Zhang Jan 2014

Degradation Of The Remanent Ferromagnetic State Under The Action Of Ferroelectric Relaxation Processes In Co/(1-X)Pmn-Xpt/Co Hybrids: Possible Implications On Cryogenic And Room-Temperature Applications, Dimosthenis Stamopoulos, M Zeibekis, G Vertsioti, Shujun Zhang

Australian Institute for Innovative Materials - Papers

Low-dimensional hybrid structures of heterogeneous constituents usually exhibit abnormal properties, a fact that makes such hybrids attractive for various cryogenic and room-temperature applications. Here, we studied Co/(1 - x)Pb(Mg 1/3 Nb 2/3 )O 3 -xPbTiO 3 /Co (Co/PMN-xPT/Co) with x=0.29 and 0.30, specifically focusing on the evolution of the remanent ferromagnetic state, m rem of the Co outer layers in the whole temperature range from 300K down to 10K, upon application of an external electric field, E ex . We observed that m rem was vulnerable to degradation through the occurrence of electric field-induced magnetic instabilities (EMIs) that appeared only …

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High Temperature, High Power Piezoelectric Composite Transducers, Hyeong Jae Lee, Shujun Zhang, Yoseph Bar-Cohen, Stewart Sherrit Jan 2014

High Temperature, High Power Piezoelectric Composite Transducers, Hyeong Jae Lee, Shujun Zhang, Yoseph Bar-Cohen, Stewart Sherrit

Australian Institute for Innovative Materials - Papers

Piezoelectric composites are a class of functional materials consisting of piezoelectric active materials and non-piezoelectric passive polymers, mechanically attached together to form different connectivities. These composites have several advantages compared to conventional piezoelectric ceramics and polymers, including improved electromechanical properties, mechanical flexibility and the ability to tailor properties by using several different connectivity patterns. These advantages have led to the improvement of overall transducer performance, such as transducer sensitivity and bandwidth, resulting in rapid implementation of piezoelectric composites in medical imaging ultrasounds and other acoustic transducers. Recently, new piezoelectric composite transducers have been developed with optimized composite components that have …

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Giant Electrocaloric Effect In Bazr0.2ti0.8o3 Thick Film, Hui-Jian Ye, Xiaoshi Qian, Dae Yong Jeong, Shujun Zhang, Yue Zhou, Wen-Zhu Shao, Liang Zhen, Q M. Zhang Jan 2014

Giant Electrocaloric Effect In Bazr0.2ti0.8o3 Thick Film, Hui-Jian Ye, Xiaoshi Qian, Dae Yong Jeong, Shujun Zhang, Yue Zhou, Wen-Zhu Shao, Liang Zhen, Q M. Zhang

Australian Institute for Innovative Materials - Papers

We report the giant electrocaloric effect (ECE) of BaZr0.2Ti0.8O3 (BZT) thick film near room temperature. The BZT thick film was fabricated by the tape casting method with the thickness of 12.0 μm. Due to the near invariant critical point composition, relaxor behavior, and the stress generated between the film and the substrate, the thick film exhibits a large adiabatic temperature drop ΔT = −7 °C under 19.5 MV/m electric field, large EC coefficient ΔT/ΔE = 0.50 x 10−6 K · m · V−1, ΔS/ΔE = 0.88 x 10−6 J · m · kg−1 · K−1 · V−1 over a wide …

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High-Order Face-Shear Modes Of Relaxor-Pbtio3 Crystals For Piezoelectric Motor Applications, Penghong Ci, Guoxi Liu, Zhijiang Chen, Shujun Zhang, Shuxiang Dong Jan 2014

High-Order Face-Shear Modes Of Relaxor-Pbtio3 Crystals For Piezoelectric Motor Applications, Penghong Ci, Guoxi Liu, Zhijiang Chen, Shujun Zhang, Shuxiang Dong

Australian Institute for Innovative Materials - Papers

The face-shear vibration modes of [011] poled Zt ± 45° cut relaxor-PT crystals and their applications for linear piezoelectric motors were investigated. Unlike piezoelectric ceramics, the rotated crystal was found to exhibit asymmetric face-shear deformations, and its two high-order face-shear modes degraded into two non-isomorphic modes. As an application example, a standing wave ultrasonic linear motor (10 × 10 × 2 mm3) operating in high-order face-shear vibration modes was developed. The motor exhibits a large driving force (1.5 N) under a low driving voltage (22 Vpp). These findings could provide guidance for design of crystal resonance devices.

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B-Nmr Of 8li+ In Rutile Tio2, R M. L Mcfadden, David L. Cortie, D J. Arseneau, T Buck, C-C Chen, M H. Dehn, S Dunsiger, R F. Kiefl, C D. P Levy, C D. Li, G D. Morris, M R. Pearson, D Samuelis, J Xiao, J Maier, W A. Macfarlane Jan 2014

B-Nmr Of 8li+ In Rutile Tio2, R M. L Mcfadden, David L. Cortie, D J. Arseneau, T Buck, C-C Chen, M H. Dehn, S Dunsiger, R F. Kiefl, C D. P Levy, C D. Li, G D. Morris, M R. Pearson, D Samuelis, J Xiao, J Maier, W A. Macfarlane

Australian Institute for Innovative Materials - Papers

We report preliminary low-energy B-NMR measurements of 8Li+ implanted in single crystal rutile TiO2 at an applied field of 6.55 T and 300 K. We observe a broad 12 kHz wide quadrupole split resonance with unresolved features and a sharp component at the Larmor frequency. The line broadening may be caused by overlapping multi-quantum transitions or motion of 8Li+ on the scale of its lifetime (1.21 s). We also find spin-lattice relaxation that is relatively fast compared to other wide band gap insulators. The origin of this fast relaxation is also likely quadrupolar and may be due to anisotropic 8Li+ …

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B-Nmr Study Of A Buried Mn &-Doped Layer In A Silicon Host, David L. Cortie, T Buck, R M. L Mcfadden, J Xiao, C D. P Levy, M H. Dehn, M R. Pearson, G D. Morris, S Dunsiger, R F. Kiefl, F Rueb, A Fuhrer, W A. Macfarlane Jan 2014

B-Nmr Study Of A Buried Mn &-Doped Layer In A Silicon Host, David L. Cortie, T Buck, R M. L Mcfadden, J Xiao, C D. P Levy, M H. Dehn, M R. Pearson, G D. Morris, S Dunsiger, R F. Kiefl, F Rueb, A Fuhrer, W A. Macfarlane

Australian Institute for Innovative Materials - Papers

Low temperature growth methods were used to encapsulate a buried Mn ¿-doping layer into a silicon host. A ¿-NMR investigation was performed of the magnetic properties in the temperature range 10-300 K using spin-polarized 8Li+. A depth-dependent broadening and shift of the NMR resonance was detected that is consistent with internal fields distributed at depths of 10-30 nm beneath the surface. At low temperatures, a negative relative shift occurred and the resonance was significantly broadened. At 300 K the line-shape could be described by a single Gaussian line, however, at 10 K the line is best approximated by a two …

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Sr Measurements Of The Magnetism Of Sr3fe2o7, W A. Macfarlane, D Peets, T Buck, K H. Chow, David L. Cortie, A Jain, C Pomerantz, C B. L Tschense, D Wang, B Keimer Jan 2014

Sr Measurements Of The Magnetism Of Sr3fe2o7, W A. Macfarlane, D Peets, T Buck, K H. Chow, David L. Cortie, A Jain, C Pomerantz, C B. L Tschense, D Wang, B Keimer

Australian Institute for Innovative Materials - Papers

We present a preliminary report of zero and transverse field ¿SR measurements in a high quality single crystal of fully oxygenated Sr3Fe2O7[1], the insulating 3d magnetic analogue of the well studied Sr3Ru2O7, in its charge-disproportionated state, through the magnetic transition to the incommensurate phase at TN ¿ 115 K. A very broad distribution of static fields below Tn yields a large (2/3) missing fraction. Rapidly damped zero field oscillations indicate a large internal field at the muon, estimated to be 0.46 T at 0 K. In the paramagnetic state, we find two muon precession frequencies at 0.25 T applied field, …

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Spin Depolarization Of Muonium In Mesoporous Silica, M H. Dehn, D J. Arseneau, M D. Bridges, T Buck, David L. Cortie, S P. Cottrell, D G. Fleming, J A. Kelly, W A. Macfarlane, M J. Maclachlan, G D. Morris, I Mckenzie, J Xiao, R F. Kiefl Jan 2014

Spin Depolarization Of Muonium In Mesoporous Silica, M H. Dehn, D J. Arseneau, M D. Bridges, T Buck, David L. Cortie, S P. Cottrell, D G. Fleming, J A. Kelly, W A. Macfarlane, M J. Maclachlan, G D. Morris, I Mckenzie, J Xiao, R F. Kiefl

Australian Institute for Innovative Materials - Papers

We report muon spin rotation/relaxation measurements of muonium in mesoporous silica (SBA-15) with a high specific surface area of 600 m2/g. Up to 70 percent of the incoming muons form muonium and escape efficiently into the open pores at all temperatures between 3 and 300K. We present evidence that the interaction with the silica surfaces involves both spin exchange and a transition to a diamagnetic state, possibly due to dangling bonds on the surface. At very low temperatures, below 20K, the interaction between muonium and the silica surfaces is suppressed due to a He film coating the surfaces. These results …

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