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Articles 1081 - 1110 of 1521

Full-Text Articles in Engineering

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 …


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 …


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 …


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 …


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.


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 …


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 …


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 …


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 …


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 …


Fabrication Of Graphene Foam Supported Carbon Nanotube/Polyaniline Hybrids For High-Performance Supercapacitor Applications, Hongxia Yang, Nan Wang, Qun Xu, Zhimin Chen, Yumei Ren, Joselito M. Razal, Jun Chen Jan 2014

Fabrication Of Graphene Foam Supported Carbon Nanotube/Polyaniline Hybrids For High-Performance Supercapacitor Applications, Hongxia Yang, Nan Wang, Qun Xu, Zhimin Chen, Yumei Ren, Joselito M. Razal, Jun Chen

Australian Institute for Innovative Materials - Papers

A large-scale, high-powered energy storage system is crucial for addressing the energy problem. The development of high-performance materials is a key issue in realizing the grid-scale applications of energy-storage devices. In this work, we describe a simple and scalable method for fabricating hybrids (graphenepyrrole/ carbon nanotube-polyaniline (GPCP)) using graphene foam as the supporting template. Graphene-pyrrole (G-Py) aerogels are prepared via a green hydrothermal route from two-dimensional materials such as graphene sheets, while a carbon nanotube/polyaniline (CNT/PANI) composite dispersion is obtained via the in situ polymerization method. The functional nanohybrid materials of GPCP can be assembled by simply dipping the prepared …


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 …


Graphene-Based Nanocomposites For Energy Storage And Conversion In Lithium Batteries, Supercapacitors And Fuel Cells, Nasir Mahmood, Chenzhen Zhang, Han Yin, Yanglong Hou Jan 2014

Graphene-Based Nanocomposites For Energy Storage And Conversion In Lithium Batteries, Supercapacitors And Fuel Cells, Nasir Mahmood, Chenzhen Zhang, Han Yin, Yanglong Hou

Australian Institute for Innovative Materials - Papers

Due to their unique properties, together with their ease of synthesis and functionalization, graphene-based materials have been showing great potential in energy storage and conversion. These hybrid structures display excellent material characteristics, including high carrier mobility, faster recombination rate and long-time stability. In this review, after a short introduction to graphene and its derivatives, we summarize the recent advances in the synthesis and applications of graphene and its derivatives in the fields of energy storage (lithium ion, lithium-air, lithium-sulphur batteries and supercapacitors) and conversion (oxygen reduction reaction for fuel cells). This article further highlights the working principles and problems hindering …


A Robust Dna Interface On A Silicon Electrode, Pauline Michaels, Muhammad Tanzirul Alam, Simone Ciampi, William Rouesnel, Stephen G. Parker, Moinul H. Choudhury, J Justin Gooding Jan 2014

A Robust Dna Interface On A Silicon Electrode, Pauline Michaels, Muhammad Tanzirul Alam, Simone Ciampi, William Rouesnel, Stephen G. Parker, Moinul H. Choudhury, J Justin Gooding

Australian Institute for Innovative Materials - Papers

Two different interfaces prepared via UV-hydrosilylation of undecylenic acid and 1,8-nonadiyne on silicon(111) have been explored to develop a robust electrochemical DNA sensor. Electrodes modified with undecylenic acid were found to stably immobilise DNA but could not resist the growth of insulating oxides, whereas 1,8-nonadiyne modified electrodes satisfy both requirements.


Polarization Alignment, Phase Transition, And Piezoelectricity Development In Polycrystalline 0.5ba(Zr0.2 Ti0.8)O3-0.5(Ba0.7 Ca0.3)Tio3, Hanzheng Guo, Brian K. Voas, Shujun Zhang, Chao Zhou, Xiaobing Ren, Scott P. Beckman, Xiaoli Tan Jan 2014

Polarization Alignment, Phase Transition, And Piezoelectricity Development In Polycrystalline 0.5ba(Zr0.2 Ti0.8)O3-0.5(Ba0.7 Ca0.3)Tio3, Hanzheng Guo, Brian K. Voas, Shujun Zhang, Chao Zhou, Xiaobing Ren, Scott P. Beckman, Xiaoli Tan

Australian Institute for Innovative Materials - Papers

The microstructural origin of the exceptionally high piezoelectric response of polycrystalline 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 is investigated using in situ transmission electron microscopy, in addition to a wide variety of bulk measurements and first-principles calculations. A direct correlation is established relating a domain wall-free state to the ultrahigh piezoelectric d33 coefficient in this BaTiO3-based composition. The results suggest that the unique single-domain state formed during electrical poling is a result of a structural transition from coexistent rhombohedral and tetragonal phases to an orthorhombic phase that has an anomalously low elastic modulus. First-principles calculations indicate that incorporating Ca2+ and Zr4+ into BaTiO3 reduces the …


Pmn-Pt Based Quaternary Piezoceramics With Enhanced Piezoelectricity And Temperature Stability, Nengneng Luo, Shujun Zhang, Qiang Li, Qingfeng Yan, Wenhui He, Yiling Zhang, Thomas R. Shrout Jan 2014

Pmn-Pt Based Quaternary Piezoceramics With Enhanced Piezoelectricity And Temperature Stability, Nengneng Luo, Shujun Zhang, Qiang Li, Qingfeng Yan, Wenhui He, Yiling Zhang, Thomas R. Shrout

Australian Institute for Innovative Materials - Papers

The phase structure, piezoelectric, dielectric, and ferroelectric properties of (0.80-x)PMN-0.10PFN-0.10PZ-xPT were investigated systematically. The morphotropic phase boundary (MPB) was confirmed to be 0.30


Element-Specific Depth Profile Of Magnetism And Stoichiometry At The La0.67sr0.33mno3/Bifeo3 Interface, Joel Bertinshaw, S Bruck, D Lott, H Fritzsche, Y Khaydukov, O Soltwedel, T Keller, E Goering, P Audehm, David L. Cortie, Wayne D. Hutchison, Q Ramasse, M Arredondo, R Maran, Vinayaka Nagarajan, Frank Klose, Clemens Ulrich Jan 2014

Element-Specific Depth Profile Of Magnetism And Stoichiometry At The La0.67sr0.33mno3/Bifeo3 Interface, Joel Bertinshaw, S Bruck, D Lott, H Fritzsche, Y Khaydukov, O Soltwedel, T Keller, E Goering, P Audehm, David L. Cortie, Wayne D. Hutchison, Q Ramasse, M Arredondo, R Maran, Vinayaka Nagarajan, Frank Klose, Clemens Ulrich

Australian Institute for Innovative Materials - Papers

Depth-sensitive magnetic, structural, and chemical characterization is important in the understanding and optimization of physical phenomena emerging at the interfaces of transition metal oxide heterostructures. In a simultaneous approach we have used polarized neutron and resonant x-ray reflectometry to determine the magnetic profile across atomically sharp interfaces of ferromagnetic La0.67Sr0.33MnO3/multiferroic BiFeO3 bilayers with subnanometer resolution. In particular, the x-ray resonant magnetic reflectivity measurements at the Fe and Mn resonance edges allowed us to determine the element-specific depth profile of the ferromagnetic moments in both the La0.67Sr0.33MnO3 and BiFeO3 layers. Our measurements indicate a magnetically diluted interface layer within the La0.67Sr0.33MnO3 …


8li+ B-Nmr In The Cubic Insulator Mgo, W A. Macfarlane, T J. Parolin, David L. Cortie, K H. Chow, M D. Hossain, R F. Kiefl, C D. P Levy, R M. L Mcfadden, G D. Morris, M R. Pearson, H Saadaoui, Z Salman, Q Song, D Wang Jan 2014

8li+ B-Nmr In The Cubic Insulator Mgo, W A. Macfarlane, T J. Parolin, David L. Cortie, K H. Chow, M D. Hossain, R F. Kiefl, C D. P Levy, R M. L Mcfadden, G D. Morris, M R. Pearson, H Saadaoui, Z Salman, Q Song, D Wang

Australian Institute for Innovative Materials - Papers

We present extensive high magnetic field B-NMR measurements of 8Li+ implanted in single crystals of MgO. The narrow resonance, consistent with a cubic 8Li+ site, likely the tetrahedral interstitital, is used routinely as a reference for shift measurements. We show the intrinsic line width is on the order of 200 Hz, allowing a frequency determination to an accuracy of a few Hz. We find no implantation energy dependence of the resonance within a few ppm, but there is evidence of slow spin dynamics in hole-burning measurements. The spin lattice relaxation is slow. The temperature dependence reveals interesting changes at low …


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 …


Interaction Of The Mu-Cyclohexadienyl Radical With Metallic (Au, Pt) Nanoparticles In Mesoporous Silica, J Xiao, D J. Arseneau, M D. Bridges, David L. Cortie, S P. Cottrell, M H. Dehn, D G. Fleming, J A. Kelly, R F. Kiefl, W A. Macfarlane, M J. Maclachlan, I Mckenzie Jan 2014

Interaction Of The Mu-Cyclohexadienyl Radical With Metallic (Au, Pt) Nanoparticles In Mesoporous Silica, J Xiao, D J. Arseneau, M D. Bridges, David L. Cortie, S P. Cottrell, M H. Dehn, D G. Fleming, J A. Kelly, R F. Kiefl, W A. Macfarlane, M J. Maclachlan, I Mckenzie

Australian Institute for Innovative Materials - Papers

SR and ALCR techniques have been used to investigate the structure and dynamics of the Mu-cyclohexadienyl radical interacting with Au and Pt metal nanoparticles (MNPs) supported in mesoporous silica (SBA-15). Surprisingly, coherent precession signals are observed and the isotropic hyperne coupling constants are almost the same in loaded and unloaded samples, implying that the electronic structure of MuC6H6 is only weakly perturbed by the presence of the MNPs. We propose the observed radicals are shielded from the metallic surfaces by a benzene coating on the MNPs. The 1 resonance is observable in MNP-loaded samples at higher temperatures than in the …


Interface Charge Doping Effects On Superconductivity Of Single-Unit-Cell Fese Films On Srtio3 Substrates, Wenhao Zhang, Zhi Li, Fangsen Li, Huimin Zhang, Jun-Ping Peng, Chenjia Tang, Qingyan Wang, Ke He, Xi Chen, Lili Wang, Xu-Cun Ma, Qi-Kun Xue Jan 2014

Interface Charge Doping Effects On Superconductivity Of Single-Unit-Cell Fese Films On Srtio3 Substrates, Wenhao Zhang, Zhi Li, Fangsen Li, Huimin Zhang, Jun-Ping Peng, Chenjia Tang, Qingyan Wang, Ke He, Xi Chen, Lili Wang, Xu-Cun Ma, Qi-Kun Xue

Australian Institute for Innovative Materials - Papers

We prepare single-unit-cell FeSe films on insulating SrTiO3 substrates by molecular beam epitaxy and investigate the evolution of their superconducting properties with annealing by in situ scanning tunneling microscopy and scanning tunneling spectroscopy and ex situ transport measurements. We find that through an annealing process, the superconductivity of 1-uc FeSe films on SrTiO3 substrates develops with the formation of stoichiometric FeSe films and is further enhanced by charge transfer from SrTiO3 substrates to FeSe films. Moreover, the superconductivity is independent of the bulk property of the SrTiO3 substrate, regardless of whether it is insulating or conductive. Our results reveal that …


Imaging The Electron-Boson Coupling In Superconducting Fese Films Using A Scanning Tunneling Microscope, Canli Song, Yi-Lin Wang, Yeping Jiang, Zhi Li, Lili Wang, Ke He, Xi Chen, Jennifer E. Hoffman, Xu-Cun Ma, Qi-Kun Xue Jan 2014

Imaging The Electron-Boson Coupling In Superconducting Fese Films Using A Scanning Tunneling Microscope, Canli Song, Yi-Lin Wang, Yeping Jiang, Zhi Li, Lili Wang, Ke He, Xi Chen, Jennifer E. Hoffman, Xu-Cun Ma, Qi-Kun Xue

Australian Institute for Innovative Materials - Papers

Scanning tunneling spectroscopy has been used to reveal signatures of a bosonic mode in the local quasiparticle density of states of superconducting FeSe films. The mode appears below Tc as a "dip-hump" feature at energy Ω ∼ 4.7kBTc beyond the superconducting gap Δ. Spectra on strained regions of the FeSe films reveal simultaneous decreases in Δ and Ω. This contrasts with all previous reports on other high-Tc superconductors, where Δ locally anticorrelates with Ω. A local strong coupling model is found to reconcile the discrepancy well, and to provide a unified picture of the electron-boson coupling in unconventional superconductors.


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 …


Core-Leaf Onion-Like Carbon/Mno2 Hybrid Nano-Urchins For Rechargeable Lithium-Ion Batteries, Ye Wang, Zhao Jun Han, Siu Fung Yu, Ran Ran Song, Huai He Song, Kostya (Ken) Ostrikov, Hui Ying Yang Nov 2013

Core-Leaf Onion-Like Carbon/Mno2 Hybrid Nano-Urchins For Rechargeable Lithium-Ion Batteries, Ye Wang, Zhao Jun Han, Siu Fung Yu, Ran Ran Song, Huai He Song, Kostya (Ken) Ostrikov, Hui Ying Yang

Australian Institute for Innovative Materials - Papers

A hybrid nano-urchin structure consisting of spherical onion-like carbon and MnO2 nanosheets is synthesized by a facile and environmentally-friendly hydrothermal method. Lithium-ion batteries incorporating the hybrid nano-urchin anode exhibit reversible lithium storage with superior specific capacity, enhanced rate capability, stable cycling performance, and nearly 100% Coulombic efficiency. These results demonstrate the effectiveness of designing hybrid nano-architectures with uniform and isotropic structure, high loading of electrochemically-active materials, and good conductivity for the dramatic improvement of lithium storage.


Magnetic Properties And Magnetocaloric Effect Of Ndmn2−Xtixsi2 Compounds, M F. Md Din, Jianli Wang, S J. Campbell, R Zeng, W D. Hutchison, M Avdeev, S J. Kennedy, S X. Dou Oct 2013

Magnetic Properties And Magnetocaloric Effect Of Ndmn2−Xtixsi2 Compounds, M F. Md Din, Jianli Wang, S J. Campbell, R Zeng, W D. Hutchison, M Avdeev, S J. Kennedy, S X. Dou

Australian Institute for Innovative Materials - Papers

The structural and magnetic properties of the intermetallic compounds NdMn2−xTixSi2(x = 0, 0.1, 0.2, and 0.3) have been studied by x-ray and high resolution neutron powder diffraction, specific heat, dc magnetization, and differential scanning calorimetry measurements over the temperature range 3–450 K. The Curie temperature and Néel temperature of NdMn2Si2 decrease from TC = 36 K and TN = 380 K to TC = 14 K and TN = 360 K, respectively, on substitution of Ti (x = 0.3) for Mn. The magnetocaloric effect …


2-(10′,10′-Dimethyl-3′-Sulfanylidene-4′- Azatricyclo[5.2.1.01,5]Decan-2′-Yl)-10,10-Dimethyl-4- Azatricyclo[5.2.1.01,5]Decane-3-Thione, Ashley Walker, Craig M. Forsyth, Patrick Perlmutter Jan 2013

2-(10′,10′-Dimethyl-3′-Sulfanylidene-4′- Azatricyclo[5.2.1.01,5]Decan-2′-Yl)-10,10-Dimethyl-4- Azatricyclo[5.2.1.01,5]Decane-3-Thione, Ashley Walker, Craig M. Forsyth, Patrick Perlmutter

Australian Institute for Innovative Materials - Papers

The title compound, C28H40N2O2S2, was obtained as a minor product from an anti-aldol reaction between the corresponding N-propionyl­thiol­actam and benzaldehyde. The asymmetric unit contains one half-molecule, which is completed by inversion symmetry. The molecule displays a nearly eclipsed conformation along the central C-C bond with a C-C-C-C- torsion angle of 20.4 (3)°.


Variation Of Pinning Mechanism And Enhancement Of Critical Current Density In Mgb2 Bulk Containing Self-Generated Coherent Mgb4 Impurity, Qi Cai, Yongchang Liu, Zongqing Ma, Huijun Li, Liming Yu Jan 2013

Variation Of Pinning Mechanism And Enhancement Of Critical Current Density In Mgb2 Bulk Containing Self-Generated Coherent Mgb4 Impurity, Qi Cai, Yongchang Liu, Zongqing Ma, Huijun Li, Liming Yu

Australian Institute for Innovative Materials - Papers

Bulk MgB2, with self-generated MgB4 pinning centers, have experienced two-step sintering process, initially at 750°C and then 900-1000°C. On the contrary to the widely accepted point that MgB 4 deteriorates superconductivity, it was found that MgB4 played a significant role in enhancing critical current density. The precipitation pattern of MgB4 was studied from the lattice scale images. It was observed that the initial coherent relation between the MgB 4 and the matrix was destroyed to become semi-coherent and even incoherent as the second-step sintering temperature increased. Owing to the lattice distortion caused by the elastic accommodation of the coherent interface, …


High-Temperature Piezoelectric Sensing, Xiaoning Jiang, Kyungrim Kim, Shujun Zhang, Joseph A. Johnson, Giovanni Salazar Jan 2013

High-Temperature Piezoelectric Sensing, Xiaoning Jiang, Kyungrim Kim, Shujun Zhang, Joseph A. Johnson, Giovanni Salazar

Australian Institute for Innovative Materials - Papers

Piezoelectric sensing is of increasing interest for high-temperature applications in aerospace, automotive, power plants and material processing due to its low cost, compact sensor size and simple signal conditioning, in comparison with other high-temperature sensing techniques. This paper presented an overview of high-temperature piezoelectric sensing techniques. Firstly, different types of high-temperature piezoelectric single crystals, electrode materials, and their pros and cons are discussed. Secondly, recent work on high-temperature piezoelectric sensors including accelerometer, surface acoustic wave sensor, ultrasound transducer, acoustic emission sensor, gas sensor, and pressure sensor for temperatures up to 1,250 °C were reviewed. Finally, discussions of existing challenges and …


Modulation Of The Properties Of Thin Ferromagnetic Films With An Externally Applied Electric Field In Ferromagnetic/Piezoelectric/Ferromagnetic Hybrids, D Stamopoulos, M Zeibekis, Shujun Zhang Jan 2013

Modulation Of The Properties Of Thin Ferromagnetic Films With An Externally Applied Electric Field In Ferromagnetic/Piezoelectric/Ferromagnetic Hybrids, D Stamopoulos, M Zeibekis, Shujun Zhang

Australian Institute for Innovative Materials - Papers

In many cases, technological advances are based on artificial low-dimensional structures of heterogeneous constituents, thus called hybrids, that when come together they provide stand-alone entities that exhibit entirely different properties. Such hybrids are nowadays intensively studied since they are attractive for both basic research and oncoming practical applications. Here, we studied hybrids constituted of piezoelectric (PE) and ferromagnetic (FM) components in the form FM/PE/FM, ultimately aiming to provide means for the controlled modulation of the properties of the FM electrodes, originating from the strain imposed to them by the PE mediator when an electric field is applied. The PE component …