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Full-Text Articles in Physical Sciences and Mathematics

Ambient Facile Synthesis Of Gram-Scale Copper Selenide Nanostructures From Commercial Copper And Selenium Powder, Xinqi Chen, Zhen Li, S X. Dou Dec 2014

Ambient Facile Synthesis Of Gram-Scale Copper Selenide Nanostructures From Commercial Copper And Selenium Powder, Xinqi Chen, Zhen Li, S X. Dou

Australian Institute for Innovative Materials - Papers

Grams of copper selenides (Cu2-xSe) were prepared from commercial copper and selenium powders in the presence of thiol ligands by a one-pot reaction at room temperature. The resultant copper selenides are a mixture of nanoparticles and their assembled nanosheets, and the thickness of nanosheets assembled is strongly dependent on the ratio of thiol ligand to selenium powder. The resultant Cu2-xSe (0 ≤ x ≤ 0.25) nanostructures were treated with hydrazine solution to remove the surface ligands and then explored as a potential thermoelectric candidate in comparison with commercial copper selenide powders. The research provides a novel …


Microscopic Model For Exchange Bias From Grain-Boundary Disorder In A Ferromagnet/Antiferromagnet Thin Film With A Nanocrystalline Microstructure, David L. Cortie, A G. Biternas, R W. Chantrell, Xiaolin Wang, Frank Klose Jan 2014

Microscopic Model For Exchange Bias From Grain-Boundary Disorder In A Ferromagnet/Antiferromagnet Thin Film With A Nanocrystalline Microstructure, David L. Cortie, A G. Biternas, R W. Chantrell, Xiaolin Wang, Frank Klose

Australian Institute for Innovative Materials - Papers

Monte Carlo spin simulations were coupled to a Voronoi microstructure-generator to predict the magnitude and behavior of exchange bias in a ferromagnet/antiferromagnet (AF) thin film bilayer with a nanocrystalline microstructure. Our model accounts for the effects of irregular grain-shapes, finite-sized particles, and the possible presence of local random-fields originating from the antiferromagnet's grain-boundary regions. As the grain-boundary represents a crystal-structure distortion, we model the local effect on the exchange constants in the Gaussian approximation which can cause regions resembling a spin glass confined to an unusual 2D topology. Although an ensemble of completely disconnected AF grains isolated by non-magnetic barriers …


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 …


Force Control Of A Tri-Layer Conducting Polymer Actuator Using Optimized Fuzzy Logic Control, Mehmet Itik, Mohammadreza Sabetghadam, Gursel Alici Jan 2014

Force Control Of A Tri-Layer Conducting Polymer Actuator Using Optimized Fuzzy Logic Control, Mehmet Itik, Mohammadreza Sabetghadam, Gursel Alici

Australian Institute for Innovative Materials - Papers

Conducting polymers actuators (CPAs) are potential candidates for replacing conventional actuators in various fields, such as robotics and biomedical engineering, due to their advantageous properties, which includes their low cost, light weight, low actuation voltage and biocompatibility. As these actuators are very suitable for use in micro-nano manipulation and in injection devices in which the magnitude of the force applied to the target is of crucial importance, the force generated by CPAs needs to be accurately controlled. In this paper, a fuzzy logic (FL) controller with a Mamdani inference system is designed to control the blocking force of a trilayer …


Uncoupled Surface Spin Induced Exchange Bias In Alpha-Mno2 Nanowires, W Li, R Zeng, Ziqi Sun, Dongliang Tian, S X. Dou Jan 2014

Uncoupled Surface Spin Induced Exchange Bias In Alpha-Mno2 Nanowires, W Li, R Zeng, Ziqi Sun, Dongliang Tian, S X. Dou

Australian Institute for Innovative Materials - Papers

We have studied the microstructure, surface states, valence fluctuations, magnetic properties, and exchange bias effect in MnO2 nanowires. High purity alpha-MnO2 rectangular nanowires were synthesized by a facile hydrothermal method with microwave-assisted procedures. The microstructure analysis indicates that the nanowires grow in the [0 0 1] direction with the (2 1 0) plane as the surface. Mn3+ and Mn2+ ions are not found in the system by X-ray photoelectron spectroscopy. The effective magnetic moment of the manganese ions fits in with the theoretical and experimental values of Mn4+ very well. The uncoupled spins in 3d(3) orbitals of the Mn4+ ions …


Charged-Controlled Separation Of Nitrogen From Natural Gas Using Boron Nitride Fullerene, Qiao Sun, Caixia Sun, Aijun Du, Zhen Li Jan 2014

Charged-Controlled Separation Of Nitrogen From Natural Gas Using Boron Nitride Fullerene, Qiao Sun, Caixia Sun, Aijun Du, Zhen Li

Australian Institute for Innovative Materials - Papers

Natural gas (the main component is methane) has been widely used as a fuel and raw material in industry. Removal of nitrogen (N2) from methane (CH4) can reduce the cost of natural gas transport and improve its efficiency. However, their extremely similar size increases the difficulty of separating N2 from CH4. In this study, we have performed a comprehensive investigation of N2 and CH4 adsorption on different charge states of boron nitride (BN) nanocage fullerene, B36N36, by using a density functional theory approach. The calculational results indicate …


Optical And Electrochemical Methods For Determining The Effective Area And Charge Density Of Conducting Polymer Modified Electrodes For Neural Stimulation, Alexander R. Harris, Paul Molino, Robert M. I Kapsa, Graeme M. Clarke, Antonio Paolini, Gordon G. Wallace Jan 2014

Optical And Electrochemical Methods For Determining The Effective Area And Charge Density Of Conducting Polymer Modified Electrodes For Neural Stimulation, Alexander R. Harris, Paul Molino, Robert M. I Kapsa, Graeme M. Clarke, Antonio Paolini, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Neural stimulation is used in the cochlear implant, bionic eye, and deep brain stimulation, which involves implantation of an array of electrodes into a patient's brain. The current passed through the electrodes is used to provide sensory queues or reduce symptoms associated with movement disorders and increasingly for psychological and pain therapies. Poor control of electrode properties can lead to suboptimal performance; however, there are currently no standard methods to assess them, including the electrode area and charge density. Here we demonstrate optical and electrochemical methods for measuring these electrode properties and show the charge density is dependent on electrode …


Hierarchical Porous Li 2 Mg(Nh)2@C Nanowires With Long Cycle Life Towards Stable Hydrogen Storage, Guanglin Xia, Yingbin Tan, Dan Li, Zaiping Guo, Hua-Kun Liu, Zongwen Liu, Xuebin Yu Jan 2014

Hierarchical Porous Li 2 Mg(Nh)2@C Nanowires With Long Cycle Life Towards Stable Hydrogen Storage, Guanglin Xia, Yingbin Tan, Dan Li, Zaiping Guo, Hua-Kun Liu, Zongwen Liu, Xuebin Yu

Australian Institute for Innovative Materials - Papers

The hierarchical porous Li2Mg(NH)2@C nanowires full of micropores, mesopores, and macropores are successfully fabricated via a single-nozzle electrospinning technique combined with in-situ reaction between the precursors, i.e., MgCl2 and LiN3, under physical restriction upon thermal annealing. The explosive decomposition of LiN3 well dispersed in the electrospun nanowires during carbothermal treatment induces a highly porous structure, which provides a favourable way for H2 delivering in and out of Li2Mg(NH)2 nanoparticles simultaneously realized by the space-confinement of the porous carbon coating. As a result, the thus-fabricated Li2Mg(NH)2 …


Α-Fe2o3/Graphene Nanocomposite As Anode Material For Sodium-Ion Batteries With Enhanced Capacity Retention, Zhijia Zhang, Yunxiao Wang, Shulei Chou, Huijun Li, Hua-Kun Liu, Jiazhao Wang Jan 2014

Α-Fe2o3/Graphene Nanocomposite As Anode Material For Sodium-Ion Batteries With Enhanced Capacity Retention, Zhijia Zhang, Yunxiao Wang, Shulei Chou, Huijun Li, Hua-Kun Liu, Jiazhao Wang

Australian Institute for Innovative Materials - Papers

Among the different energy storage systems, rechargeable lithium-ion batteries (LIBs) have been widely applied in various portable electronic devices due to their high energy densities, long cycle life, and lack of significant memory effect [1]. For wide-scale implementation of renewable energy, LIBs, however, face challenges related to their safety, lifetime, and cost. Based on the wide availability and low cost of sodium, sodium-ion batteries (SIBs) have the potential for meeting the demands of large-scale and sustainable applications. Many cathode materials have been proposed, whereas only a few anode materials have been investigated for SIBs [2]. The sodium ion (1.02 Å) …


Liquid Crystalline Graphene Oxide/Pedot: Pss Self-Assembled 3d Architecture For Binder-Free Supercapacitor Electrodes, Md. Monirul Islam, Alfred T. Chidembo, Seyed Hamed Aboutalebi, Dean Cardillo, Hua-Kun Liu, Konstantin K. Konstantinov, S X. Dou Jan 2014

Liquid Crystalline Graphene Oxide/Pedot: Pss Self-Assembled 3d Architecture For Binder-Free Supercapacitor Electrodes, Md. Monirul Islam, Alfred T. Chidembo, Seyed Hamed Aboutalebi, Dean Cardillo, Hua-Kun Liu, Konstantin K. Konstantinov, S X. Dou

Australian Institute for Innovative Materials - Papers

Binder-free self-assembled 3D architecture electrodes have been fabricated by a novel convenient method. Liquid crystalline graphene oxide was used as precursor to interact with poly(3,4-ethylene-dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) in dispersion in order to form a conductive polymer entrapped, self-assembled layer-by-layer structure. This advanced network containing PEDOT:PSS enabled us to ascribe the superior electrochemical properties of particular graphene sheets. This layer-by-layer self-assembled 3D architecture of best performing composite (reduced graphene oxide-PEDOT:PSS 25) showed excellent electrochemical performance of 434 F g−1 through chemical treatment. To highlight these advances, we further explored the practicality of the as-prepared electrode by varying the composite material content. …


Large Scale Production Of Novel G-C3n4 Micro Strings With High Surface Area And Versatile Photodegradation Ability, Muhammad Nawaz Tahir, Chuanbao Cao, Faheem K. Butt, Sajid Butt, Faryal Idrees, Zulfiqar Ali, Imran Aslam, M Tanveer, Asif Mahmood, Nasir Mahmood Jan 2014

Large Scale Production Of Novel G-C3n4 Micro Strings With High Surface Area And Versatile Photodegradation Ability, Muhammad Nawaz Tahir, Chuanbao Cao, Faheem K. Butt, Sajid Butt, Faryal Idrees, Zulfiqar Ali, Imran Aslam, M Tanveer, Asif Mahmood, Nasir Mahmood

Australian Institute for Innovative Materials - Papers

An easy, scalable and environmentally benign chemical method has been developed to synthesize micro strings of graphitic-C3N4 (msg-C3N4) through pre-treatment of melamine with HNO 3 in alkaline solvent at low temperature. This methodology results in a unique string type morphology of msg-C3N4 with higher surface area. These msg-C3N4 micro strings were used as a photocatalyst under visible light for photodegradation of rhodamine B, methyl blue and methyl orange. The msg-C3N4 shows enhanced photodegradation efficiency due to its high surface area and favourable bandgap. The first order rate constant for msg-C3N4 was measured which confirms the higher performance of msg-C3N4 in …


Microemulsion-Assisted Synthesis Of Nanosized Li-Mn-O Spinel Cathodes For High-Rate Lithium-Ion Batteries, Xianhong Rui, Wenping Sun, Qingyu Yan, Tuti M. Lim, Maria Skyllas-Kazacos Jan 2014

Microemulsion-Assisted Synthesis Of Nanosized Li-Mn-O Spinel Cathodes For High-Rate Lithium-Ion Batteries, Xianhong Rui, Wenping Sun, Qingyu Yan, Tuti M. Lim, Maria Skyllas-Kazacos

Australian Institute for Innovative Materials - Papers

Li1.16Mn1.84O4 nanoparticles (50-90 nm) with cubic spinel structure are synthesized by combining a microemulsion process to produce ultrafine Mn(OH)2 nanocrystals (3-8 nm) with a solid-state lithiation step. The nanostructured lithium-rich Li1.16Mn1.84O4 shows stable cycling performance and superior rate capabilities as compared with the corresponding bulk material, for example, the nano-sized Li1.16Mn1.84O4 electrode shows stable reversible capacities of 74 mAhg-1 during the 1000th cycle at a high rate of 40 C between 3.0 and 4.5 V. In addition, Li1.16Mn1.84O4 nanoparticles also show high Li storage properties over an enlarged voltage window of 2.0-4.5 V with high capacities and stable cyclability, for …


Template Free Synthesis Of Cus Nanosheet-Based Hierarchical Microspheres: An Efficient Natural Light Driven Photocatalyst, M Tanveer, Chuanbao Cao, Zulfiqar Ali, Imran Aslam, Faryal Idrees, Waheed S. Khan, Faheem K. Butt, Muhammad Nawaz Tahir, Nasir Mahmood Jan 2014

Template Free Synthesis Of Cus Nanosheet-Based Hierarchical Microspheres: An Efficient Natural Light Driven Photocatalyst, M Tanveer, Chuanbao Cao, Zulfiqar Ali, Imran Aslam, Faryal Idrees, Waheed S. Khan, Faheem K. Butt, Muhammad Nawaz Tahir, Nasir Mahmood

Australian Institute for Innovative Materials - Papers

Well controlled nanosheets-based hierarchical microspheres (NSHMS) of pure covellite phase CuS were synthesized using a facile PVP assisted solvothermal process. The reaction conditions were optimized using various amounts of PVP to develop unique hierarchical structured hollow microspheres. CuS hollow structures have a bandgap of ~1.97 eV. These mesoporous structures exhibit excellent photocatalytic activity in degradation of organic dyes (Methylene Blue) under natural light in comparison to other structures of copper sulphide. These photocatalysts show extraordinary reusability with over 96.5% degradation of organic dye after 6th cycle. A "bottom-up" assembly was successfully developed to synthesize hollow microspheres with unique and well …


Hydrostatic Piezoelectric Properties Of [011] Poled Pb(Mg 1/3nb2/3)O3-Pbtio3 Single Crystals And 2-2 Lamellar Composites, Lili Li, Shujun Zhang, Zhuo Xu, Xuecang Geng, Fei Wen, Jun Luo, Thomas R. Shrout Jan 2014

Hydrostatic Piezoelectric Properties Of [011] Poled Pb(Mg 1/3nb2/3)O3-Pbtio3 Single Crystals And 2-2 Lamellar Composites, Lili Li, Shujun Zhang, Zhuo Xu, Xuecang Geng, Fei Wen, Jun Luo, Thomas R. Shrout

Australian Institute for Innovative Materials - Papers

The hydrostatic piezoelectric properties of [011] poled Pb(Mg 1/3Nb2/3)O3-PbTiO3 (PMN-PT) crystals and corresponding 2-2 crystal/epoxy composites were investigated. The crystal volume ratio and compositional dependencies of the hydrostatic charge and voltage coefficients (dh and gh) and hydrostatic figure of merit (FOM) dh x gh were determined, where large FOM value of 3.2 pm2/N with high stability as a function of hydrostatic pressure was achieved for rhombohedral crystal composites. In addition, the stress amplification effects of the face-plate and different epoxy matrixes were investigated, with maximum FOM value being on the order of 92 pm2/N, indicating that 2-2 crystal/epoxy composites are …


Β-Detected Nmr Of 8li+ In Bi, Sb, And The Topological Insulator Bi0.9sb0.1, W A. Macfarlane, C B. L Tschense, T Buck, K H. Chow, David L. Cortie, A Hariwal, R F. Kiefl, D Koumoulis, C D. P Levy, I Mckenzie, F H. Mcgee, G D. Morris, M R. Pearson, Q Song, D Wang, Y S. Hor, R J. Cava Jan 2014

Β-Detected Nmr Of 8li+ In Bi, Sb, And The Topological Insulator Bi0.9sb0.1, W A. Macfarlane, C B. L Tschense, T Buck, K H. Chow, David L. Cortie, A Hariwal, R F. Kiefl, D Koumoulis, C D. P Levy, I Mckenzie, F H. Mcgee, G D. Morris, M R. Pearson, Q Song, D Wang, Y S. Hor, R J. Cava

Australian Institute for Innovative Materials - Papers

We report the NMR Knight shift and spin-lattice relaxation of Li8+ implanted ¿100 nm into single crystals of semimetallic Sb, Bi, and topologically insulating Bi0.9Sb0.1. We find small negative shifts (of order 100 ppm) in all three. In the insulator, the shift is nearly temperature independent, while in Bi and Sb it becomes more negative at low temperature without following the bulk susceptibility, suggesting two distinct temperature dependent contributions, possibly from the orbital and spin response. However, a simple model is unable to account for the observed shift. The spin-lattice relaxation differs in both scale and temperature dependence in all …


Dichotomy Of The Electronic Structure And Superconductivity Between Single-Layer And Double-Layer Fese/Srtio3 Films, Xu Liu, Defa Liu, Wenchao Zhang, Junfeng He, Lin Zhao, Shaolong He, Daixiang Mou, Fangsen Li, Chenjia Tang, Zhi Li, Lili Wang, Yingying Peng, Yan Liu, Chaoyu Chen, Guodong Liu, Xiaoli Dong, Jun Zhang, Chuangtian Chen, Zuyan Xu, Xi Chen, Xu-Cun Ma, Qi-Kun Xue, X J. Zhou Jan 2014

Dichotomy Of The Electronic Structure And Superconductivity Between Single-Layer And Double-Layer Fese/Srtio3 Films, Xu Liu, Defa Liu, Wenchao Zhang, Junfeng He, Lin Zhao, Shaolong He, Daixiang Mou, Fangsen Li, Chenjia Tang, Zhi Li, Lili Wang, Yingying Peng, Yan Liu, Chaoyu Chen, Guodong Liu, Xiaoli Dong, Jun Zhang, Chuangtian Chen, Zuyan Xu, Xi Chen, Xu-Cun Ma, Qi-Kun Xue, X J. Zhou

Australian Institute for Innovative Materials - Papers

The latest discovery of possible high-temperature superconductivity in the single-layer FeSe film grown on a SrTiO3 substrate has generated much attention. Initial work found that, while the single-layer FeSe/SrTiO3 film exhibits a clear signature of superconductivity, the double-layer film shows an insulating behaviour. Such a marked layer-dependent difference is surprising and the underlying origin remains unclear. Here we report a comparative angleresolved photoemission study between the single-layer and double-layer FeSe/SrTiO3 films annealed in vacuum. We find that, different from the single-layer FeSe/SrTiO3 film, the double-layer FeSe/SrTiO3 film is hard to get doped and remains in the semiconducting/ insulating state under …


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 …


Direct Synthesis Of Rgo/Cu2o Composite Films On Cu Foil For Supercapacitors, Xiangmao Dong, Kun Wang, Chongjun Zhao, Xiuzhen Qian, Shi Chen, Zhen Li, Hua-Kun Liu, S X. Dou Jan 2014

Direct Synthesis Of Rgo/Cu2o Composite Films On Cu Foil For Supercapacitors, Xiangmao Dong, Kun Wang, Chongjun Zhao, Xiuzhen Qian, Shi Chen, Zhen Li, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

Reduced graphene oxide/cuprous oxide (RGO/Cu2O) composite films were directly synthesized on the surface of copper foil substrates through a straight redox reaction between GO and Cu foil via a hydrothermal approach. Characterization of the resultant composites with X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and field emission scanning electron microscope (FESEM) confirms the formation of Cu2O and reduction of GO, in which Cu2O nanoparticles were well covered by RGO. The resultant composites (referred to as RGO/Cu2O/Cu) were directly used as electrodes for supercapacitors, and their electrochemical performance was assessed by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectrometry …


Formation And Processability Of Liquid Crystalline Dispersion Graphene Oxide, Rouhollah Jalili, Seyed Hamed Aboutalebi, Dorna Esrafilzadeh, Konstantin Konstantinov, Joselito M. Razal, Simon E. Moulton, Gordon G. Wallace Jan 2014

Formation And Processability Of Liquid Crystalline Dispersion Graphene Oxide, Rouhollah Jalili, Seyed Hamed Aboutalebi, Dorna Esrafilzadeh, Konstantin Konstantinov, Joselito M. Razal, Simon E. Moulton, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Rational control over the formation and processability, and consequently final properties of graphene oxide liquid crystalline dispersions has been a long-standing goal in the development of bottom-up device fabrication processes. Here we report, the principal conditions through which such levels of control can be exercised to fine-tune dispersion properties for further processing.


Exchange Interaction Mediated Ferroelectricity In Multiferroic Mntio3 With Anisotropic Orbital Hybridization And Hole Delocalization, Shiwei Chen, Paoan Lin, Horngtay Jeng, S W. Fu, Jennmin Lee, Jyhfu Lee, Chihwen Pao, Hirofumi Ishii, Kuding Tsuei, Nozomu Hiraoka, Dapeng Chen, S X. Dou, Xiaolin Wang, Kueihtzu Lu, Jinming Chen Jan 2014

Exchange Interaction Mediated Ferroelectricity In Multiferroic Mntio3 With Anisotropic Orbital Hybridization And Hole Delocalization, Shiwei Chen, Paoan Lin, Horngtay Jeng, S W. Fu, Jennmin Lee, Jyhfu Lee, Chihwen Pao, Hirofumi Ishii, Kuding Tsuei, Nozomu Hiraoka, Dapeng Chen, S X. Dou, Xiaolin Wang, Kueihtzu Lu, Jinming Chen

Australian Institute for Innovative Materials - Papers

We present the orbital structure of MnTiO3 with polarization dependent x-ray absorption and resonant x-ray emission spectra accompanied with electronic structure calculations. The results clearly indicate a strongly anisotropic O 2p-Mn 3d orbital hybridization whereas the Mn 3d hole state shows a highly delocalized characteristic ascribed to the 3d-4p mixing. The extended Mn 4p orbital could enhance the exchange interaction between Mn (3d)-O (2p)-Mn (3d) leading to an asymmetric charge distribution in Mn-O bonds. The delocalized characteristic of Mn 3d holes is indispensable to the mechanism of spin-dependent-metal-ligand hybridization to explain magnetically induced ferroelectricity.


Fast And Rewritable Colloidal Assembly Via Field Synchronized Particle Swapping, Pietro Tierno, Tom H. Johansen, Thomas M. Fischer Jan 2014

Fast And Rewritable Colloidal Assembly Via Field Synchronized Particle Swapping, Pietro Tierno, Tom H. Johansen, Thomas M. Fischer

Australian Institute for Innovative Materials - Papers

We report a technique to realize reconfigurable colloidal crystals by using the controlled motion of particle defects above an externally modulated magnetic substrate. The transport of particles is induced by applying a uniform rotating magnetic field to a ferrite garnet film characterized by a periodic lattice of magnetic bubbles. For filling factor larger than one colloid per bubble domain, the particle current arises from propagating defects where particles synchronously exchange their position when passing from one occupied domain to the next. The amplitude of an applied alternating magnetic field can be used to displace the excess particles via a swapping …


Pressure Induced Magneto-Structural Phase Transitions In Layered Rmn2x2 Compounds (Invited), Shane Kennedy, Jianli Wang, Stewart Campbell, Michael Hofmann, S X. Dou Jan 2014

Pressure Induced Magneto-Structural Phase Transitions In Layered Rmn2x2 Compounds (Invited), Shane Kennedy, Jianli Wang, Stewart Campbell, Michael Hofmann, S X. Dou

Australian Institute for Innovative Materials - Papers

We have studied a range of pseudo-ternaries derived from the parent compound PrMn2 Ge 2, substituting for each constituent element with a smaller one to contract the lattice. This enables us to observe the magneto-elastic transitions that occur as the Mn-Mn nearest neighbour distance is reduced and to assess the role of Pr on the magnetism. Here, we report on the PrMn2 Ge 2−xSix, Pr1−xYxMn2 Ge 2, and PrMn2−xFex Ge 2 systems. The pressure produced by chemical substitution in these pseudo-ternaries is inherently non-uniform, with local pressure variations dependent on the local atomic distribution. We find that concentrated chemical substitution …


Recent Progress In Thermoelectric Materials, Chao Han, Zhen Li, S X. Dou Jan 2014

Recent Progress In Thermoelectric Materials, Chao Han, Zhen Li, S X. Dou

Australian Institute for Innovative Materials - Papers

Direct conversion of heat into electricity through advanced thermoelectric (TE) materials has been one of the most attractive solutions to the severe environmental and energy issues facing humanity. In recent years, great progress has been made in improving their dimensionless figure of merit (ZT), which determines the conversion efficiency of TE devices. ZT is related to three “interlocked” factors—the Seebeck coefficient, electrical conductivity, and thermal conductivity. These three factors are interdependent in bulk TE materials, and altering one changes the other two. The difficulty in simultaneously optimizing them caused TE research to stagnate, until great reductions in thermal conductivity were …


Large Magnetoelectric Coupling In Magnetically Short-Range Ordered Bi5ti3feo15 Film, Hongyang Zhao, Hideo Kimura, Zhenxiang Cheng, Minoru Osada, Jianli Wang, Xiaolin Wang, S X. Dou, Yan Liu, Jianding Yu, Takao Matsumoto, Tetsuya Tohei, Naoya Shibata, Yuichi Ikuhara Jan 2014

Large Magnetoelectric Coupling In Magnetically Short-Range Ordered Bi5ti3feo15 Film, Hongyang Zhao, Hideo Kimura, Zhenxiang Cheng, Minoru Osada, Jianli Wang, Xiaolin Wang, S X. Dou, Yan Liu, Jianding Yu, Takao Matsumoto, Tetsuya Tohei, Naoya Shibata, Yuichi Ikuhara

Australian Institute for Innovative Materials - Papers

Multiferroic materials, which offer the possibility of manipulating the magnetic state by an electric field or vice versa, are of great current interest. However, single-phase materials with such cross-coupling properties at room temperature exist rarely in nature; new design of nano-engineered thin films with a strong magneto-electric coupling is a fundamental challenge. Here we demonstrate a robust room-temperature magneto-electric coupling in a bismuth-layer-structured ferroelectric Bi5Ti3FeO15 with high ferroelectric Curie temperature of ~1000 K. Bi5Ti3FeO15 thin films grown by pulsed laser deposition are single-phase layered perovskit with nearly (00l)-orientation. Room-temperature multiferroic behavior is demonstrated by a large modulation in magneto-polarization and …


High-Performance Sodium-Ion Batteries And Sodium-Ion Pseudocapacitors Based On Mos2/Graphene Composites, Yunxiao Wang, Shulei Chou, David Wexler, Hua-Kun Liu, S X. Dou Jan 2014

High-Performance Sodium-Ion Batteries And Sodium-Ion Pseudocapacitors Based On Mos2/Graphene Composites, Yunxiao Wang, Shulei Chou, David Wexler, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

Sodium-ion energy storage, including sodium-ion batteries (NIBs) and electrochemical capacitive storage (NICs), is considered as a promising alternative to lithium-ion energy storage. It is an intriguing prospect, especially for large-scale applications, owing to its low cost and abundance. MoS2 sodiation/desodiation with Na ions is based on the conversion reaction, which is not only able to deliver higher capacity than the intercalation reaction, but can also be applied in capacitive storage owing to its typically sloping charge/discharge curves. Here, NIBs and NICs based on a graphene composite (MoS2/G) were constructed. The enlarged d-spacing, a contribution of the graphene matrix, and the …


Fully Roll-To-Roll Gravure Printable Wireless (13.56 Mhz) Sensor-Signage Tags For Smart Packaging, Hwiwon Kang, Hyejin Park, Yongsu Park, Minhoon Jung, Byung Chul Kim, Gordon G. Wallace, Gyoujin Cho Jan 2014

Fully Roll-To-Roll Gravure Printable Wireless (13.56 Mhz) Sensor-Signage Tags For Smart Packaging, Hwiwon Kang, Hyejin Park, Yongsu Park, Minhoon Jung, Byung Chul Kim, Gordon G. Wallace, Gyoujin Cho

Australian Institute for Innovative Materials - Papers

Integration of sensing capabilities with an interactive signage through wireless communication is enabling the development of smart packaging wherein wireless (13.56 MHz) power transmission is used to interlock the smart packaging with a wireless (13.56 MHz) reader or a smart phone. Assembly of the necessary componentry for smart packaging on plastic or paper foils is limited by the manufacturing costs involved with Si based technologies. Here, the issue of manufacturing cost for smart packaging has been obviated by materials that allow R2R (roll-to-roll) gravure in combination with R2R coating processes to be employed. R2R gravure was used to print the …


Applications Of Scanning Electrochemical Microscopy (Secm) For Local Characterization Of Az31 Surface During Corrosion In A Buffered Media, Sina S. Jamali, Simon E. Moulton, Dennis E. Tallman, Maria Forsyth, Jan Weber, Gordon G. Wallace Jan 2014

Applications Of Scanning Electrochemical Microscopy (Secm) For Local Characterization Of Az31 Surface During Corrosion In A Buffered Media, Sina S. Jamali, Simon E. Moulton, Dennis E. Tallman, Maria Forsyth, Jan Weber, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Different modes of scanning electrochemical mapping (SECM) such as surface generation/tip collection (SG/TC), amperometry, AC-SECM and potentiometry were employed to characterize the active/passive domains, hydrogen gas (H2) evolution and local pH on a corroding surface of AZ31 in simulated biological fluid (SBF). It was found that the main domains of H2 evolution are associated with lower insulating properties of the surface as well as higher local pH. The near surface pH was found to be highly alkaline indicating that, even in a buffered solution such as SBF, the local pH on a corroding AZ31 surface can be significantly different to …


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 …


Graphene Oxide Dispersions: Tuning Rheology To Enable Fabrication, Sina Naficy, Rouhollah Jalili, Seyed Hamed Aboutalebi, Robert A. Gorkin Iii, Konstantin Konstantinov, Peter C. Innis, Geoffrey M. Spinks, Philippe Poulin, Gordon G. Wallace Jan 2014

Graphene Oxide Dispersions: Tuning Rheology To Enable Fabrication, Sina Naficy, Rouhollah Jalili, Seyed Hamed Aboutalebi, Robert A. Gorkin Iii, Konstantin Konstantinov, Peter C. Innis, Geoffrey M. Spinks, Philippe Poulin, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Here, we show that graphene oxide (GO) dispersions exhibit unique viscoelastic properties, making them a new class of soft materials. The fundamental insights accrued here provide the basis for the development of fabrication protocols for these two-dimensional soft materials, in a diverse array of processing techniques.


Bioactive Coatings For Orthopaedic Implants-Recent Trends In Development Of Implant Coatings, Bill G. X Zhang, Damian E. Myers, Gordon G. Wallace, Milan Brandt, Peter F. M Choong Jan 2014

Bioactive Coatings For Orthopaedic Implants-Recent Trends In Development Of Implant Coatings, Bill G. X Zhang, Damian E. Myers, Gordon G. Wallace, Milan Brandt, Peter F. M Choong

Australian Institute for Innovative Materials - Papers

Joint replacement is a major orthopaedic procedure used to treat joint osteoarthritis. Aseptic loosening and infection are the two most significant causes of prosthetic implant failure. The ideal implant should be able to promote osteointegration, deter bacterial adhesion and minimize prosthetic infection. Recent developments in material science and cell biology have seen the development of new orthopaedic implant coatings to address these issues. Coatings consisting of bioceramics, extracellular matrix proteins, biological peptides or growth factors impart bioactivity and biocompatibility to the metallic surface of conventional orthopaedic prosthesis that promote bone ingrowth and differentiation of stem cells into osteoblasts leading to …