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Full-Text Articles in Engineering

Efficient Subversion Of Symmetric Encryption With Random Initialization Vector, Joon Sang Baek, Ilsun You Jan 2016

Efficient Subversion Of Symmetric Encryption With Random Initialization Vector, Joon Sang Baek, Ilsun You

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents an efficient subverted symmetric encryption scheme, which outputs a random initialization vector (IV). Compared with the available scheme of the same kind in the literature, our attack provides a saboteur (big brother) with much faster recovery of a key used in a victim's symmetric encryption scheme. Our result implies that care must be taken when a symmetric encryption scheme with a random IV such as randomized CBC is deployed.


Preliminary Observations Of The Effect Of Plate Roughness And Particle Size On The Determination Of Wall Friction, David B. Hastie, Wendy G. Halford Jan 2016

Preliminary Observations Of The Effect Of Plate Roughness And Particle Size On The Determination Of Wall Friction, David B. Hastie, Wendy G. Halford

Faculty of Engineering and Information Sciences - Papers: Part B

The determination of wall friction angle for bulk materials is vital in applications such as; bin and hopper design, conveyor transfer chutes, rail wagon unloading and any other use where bulk materials flow over a surface. It is generally accepted that the rougher the wall surface, the higher the wall friction angle. This paper will present an investigation of wall samples with various surface finishes using a translational shear tester (based on the design by Jenike). Five aluminium plates; one with a 'smooth' surface and the other four with milled grooves of varying spacing and depth to produce regular 'roughness' …


On The Difficulties Of Quantifying The Segregation Of Fine Powder Blends, David B. Hastie Jan 2016

On The Difficulties Of Quantifying The Segregation Of Fine Powder Blends, David B. Hastie

Faculty of Engineering and Information Sciences - Papers: Part B

This paper reports on the difficulties of finding an accurate and consistent test method for quantifying the segregation of two fine powders. The background is from an industrial project investigating the feasibility of blending pulverised coal and crushed nickel ore in a bulk materials handling application, to ultimately produce nickel. The feasibility of combining the two products early in the process was investigated due to the blend requiring various different handling methods throughout the industrial process, making the constituent products susceptible to segregation. In the experimental investigation, representative samples of each bulk material were used to create a range of …


Estimating The Compression Behaviour Of Metal-Rich Clays Via A Disturbed State Concept (Dsc) Model, Ri-Dong Fan, Martin D. Liu, Yan Jun Du, Suksun Horpibulsuk Jan 2016

Estimating The Compression Behaviour Of Metal-Rich Clays Via A Disturbed State Concept (Dsc) Model, Ri-Dong Fan, Martin D. Liu, Yan Jun Du, Suksun Horpibulsuk

Faculty of Engineering and Information Sciences - Papers: Part B

Many studies have been made on the compression behaviour of clay exposed to metal-rich liquids (metal-rich clay) because metal contamination of clay is found worldwide and increasingly poses as an environmental risk. However, the study on predicting the compression behaviour of contaminated clay with various metal concentrations is very limited. In this paper, a general compression model of the metal-rich clays is proposed based on a general Disturbed State Concept (DSC) compression model. A simplified form of the general model is proposed, and validated based on the compression behaviour of metal-rich clays with various metal concentrations in the pore liquid. …


Detecting Visual Spoofing Using Classical Cryptanalysis Methods In Plagiarism Detection Systems, Yang-Wai Chow, Willy Susilo, Ilung Pranata, Ari Moesriami Barmawi Jan 2016

Detecting Visual Spoofing Using Classical Cryptanalysis Methods In Plagiarism Detection Systems, Yang-Wai Chow, Willy Susilo, Ilung Pranata, Ari Moesriami Barmawi

Faculty of Engineering and Information Sciences - Papers: Part B

No abstract provided.


Dynamic Magneto-Optical Imaging Of Superconducting Thin Films, Frederick Wells, Alexey V. Pan, Stephen Wilson, Igor Golovchanskiy, Sergey Fedoseev, Anatoly B. Rosenfeld Jan 2016

Dynamic Magneto-Optical Imaging Of Superconducting Thin Films, Frederick Wells, Alexey V. Pan, Stephen Wilson, Igor Golovchanskiy, Sergey Fedoseev, Anatoly B. Rosenfeld

Australian Institute for Innovative Materials - Papers

We present a novel method for analysis of superconducting thin films using dynamic magneto-optical imaging, revealing hallmarks of flux penetration with temporal resolution around 1 ms (in the present work) or better. This method involves investigation of transient field and dynamic current distributions, which are calculated by an inversion procedure on the Biot-Savart Law, which we show to be valid under dynamic conditions. We compare and discuss the flux front penetration speed and evolution of current distribution in high quality YBa2Cu3O${}_{7-\delta }$ thin films with that of samples deliberately damaged in such a way as to reduce critical current density …


Ambient Synthesis Of One-/Two-Dimensional Cuagse Ternary Nanotubes As Counter Electrodes Of Quantum-Dot-Sensitized Solar Cells, Xin Qi Chen, Yang Bai, Zhen Li, Lian Zhou Wang, S X. Dou Jan 2016

Ambient Synthesis Of One-/Two-Dimensional Cuagse Ternary Nanotubes As Counter Electrodes Of Quantum-Dot-Sensitized Solar Cells, Xin Qi Chen, Yang Bai, Zhen Li, Lian Zhou Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. One-/two-dimensional ternary CuAgSe nanotubes (NTs) were successfully prepared from copper selenide (Cu2-xSe) NTs at room temperature within a short reaction time by the facile cation-exchange approach. Cation exchange leads to the transformation of the crystal structure from cubic into orthorhombic and/or tetragonal with good retention of morphology. The exchange reactions are spontaneous owing to large negative changes of the Gibbs free energy. The effects of parameters such as reaction time, precursor source, and precursor ratio on the exchange reaction were investigated. The resultant CuAgSe NTs were explored as counter electrodes (CEs) of …


Ambient Synthesis Of A Multifunctional 1d/2d Hierarchical Ag-Ag2s Nanowire/Nanosheet Heterostructure With Diverse Applications, Jinyan Xiong, Chao Han, Weijie Li, Qiao Sun, Jun Chen, Shulei Chou, Zhen Li, S X. Dou Jan 2016

Ambient Synthesis Of A Multifunctional 1d/2d Hierarchical Ag-Ag2s Nanowire/Nanosheet Heterostructure With Diverse Applications, Jinyan Xiong, Chao Han, Weijie Li, Qiao Sun, Jun Chen, Shulei Chou, Zhen Li, S X. Dou

Australian Institute for Innovative Materials - Papers

A new type of unique 1D/2D hierarchical Ag-Ag2S heterostructures is fabricated by an extremely simple solution route under ambient conditions. The morphology, size, crystal structure and composition of the products were comprehensively investigated, and it was found that the reaction time and the amount of S powder play crucial roles in the formation of well-defined 1D/2D hierarchical Ag-Ag2S heterostructures. The diffusion and Ostwald ripening processes dominate the evolution of the heterostructure. The resultant 1D/2D Ag-Ag2S hybrids exhibit great potential in Li/Na ion battery anodes, SERS detection and decoloration towards organic dyes.


Silicon Monoxide-A Convenient Precursor For Large Scale Synthesis Of Near Infrared Emitting Monodisperse Silicon Nanocrystals, Wei Sun, Chenxi Qian, Xiao Sherri Cui, Liwei Wang, Muan Wei, Gilberto Casillas, Amr S. Helmy, Geoffrey A. Ozin Jan 2016

Silicon Monoxide-A Convenient Precursor For Large Scale Synthesis Of Near Infrared Emitting Monodisperse Silicon Nanocrystals, Wei Sun, Chenxi Qian, Xiao Sherri Cui, Liwei Wang, Muan Wei, Gilberto Casillas, Amr S. Helmy, Geoffrey A. Ozin

Australian Institute for Innovative Materials - Papers

While silicon nanocrystals (ncSi) embedded in silicon dioxide thin films have been intensively studied in physics, the potential of batch synthesis of silicon nanocrystals from the solid-state disproportionation of SiO powder has not drawn much attention in chemistry. Herein we describe some remarkable effects observed in the diffraction, microscopy and spectroscopy of SiO powder upon thermal processing in the temperature range 850-1100 °C. Quantum confinement effects and structural changes of the material related to the size of the silicon nanocrystals nucleated and grown in this way were established by Photoluminescence (PL), Raman, FTIR and UV-Visible spectroscopy, PXRD and STEM, pinpointing …


Significant Enhancement Of The Cycling Performance And Rate Capability Of The P/C Composite Via Chemical Bonding (P-C), Weijie Li, Shulei Chou, Jiazhao Wang, Hua-Kun Liu, S X. Dou Jan 2016

Significant Enhancement Of The Cycling Performance And Rate Capability Of The P/C Composite Via Chemical Bonding (P-C), Weijie Li, Shulei Chou, Jiazhao Wang, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

Among anode materials for sodium ion batteries, red phosphorus is a very promising one due to its abundant reserves, low-cost and high theoretical capacity of 2600 mA h g-1. However, its huge volume expansion on sodiation (∼490%) and poor conductivity leads to dramatic capacity decay, restraining its practical application. To improve the electrochemical performance, here, we prepared a red phosphorus and graphene nanoplate composite using cheap red P and natural graphite as the starting materials via a simple and scalable ball-milling method. The phosphorus-carbon bond formed during the milling process improves the electrical connectivity between P particles and graphene nanoplates, …


Controllable Synthesis Of Few-Layered And Hierarchically Porous Boron Nitride Nanosheets, Feng Xiao, Zhixin Chen, Gilberto Casillas, Christopher Richardson, Huijun Li, Zhenguo Huang Jan 2016

Controllable Synthesis Of Few-Layered And Hierarchically Porous Boron Nitride Nanosheets, Feng Xiao, Zhixin Chen, Gilberto Casillas, Christopher Richardson, Huijun Li, Zhenguo Huang

Australian Institute for Innovative Materials - Papers

Few-layered porous boron nitride nanosheets (BNNS) have been prepared using a dynamic magnesium diboride (MgB2) template and ammonium chloride (NH4Cl) etchant. Magnesium-based intermediates serve as layer separators in the synthesis and prevent extensive aggregation, resulting in few-layered BNNS. The resultant BNNS are hierarchically porous and show good CO2/N2 adsorption selectivity.


Intrinsically Core-Shell Plasmonic Dielectric Nanostructures With Ultrahigh Refractive Index, Zengji Yue, Boyuan Cai, Lan Wang, Xiaolin Wang, Min Gu Jan 2016

Intrinsically Core-Shell Plasmonic Dielectric Nanostructures With Ultrahigh Refractive Index, Zengji Yue, Boyuan Cai, Lan Wang, Xiaolin Wang, Min Gu

Australian Institute for Innovative Materials - Papers

Topological insulators are a new class of quantum material s with metallic (edge) surface states and insulating bulk states. They demonstrate a variety of novel electronic and optical properties, which make them highly promising electronic, spintronic, and optoelectronic materials. We report on a novel conic plasmonic nanostructure that is made of bulk-insulating topological insulators and has an intrinsic core-shell formation. The insulating (dielectric) core of the nanocone displays an ultrahigh refractive index of up to 5.5 in the near-infrared frequency range. On the metallic shell, plasmonic response and strong backward light scattering were observed in the visible frequency range. Through …


Toward Biodegradable Mg-Air Bioelectric Batteries Composed Of Silk Fibroin-Polypyrrole Film, Xiaoteng Jia, Caiyun Wang, Chen Zhao, Yu Ge, Gordon G. Wallace Jan 2016

Toward Biodegradable Mg-Air Bioelectric Batteries Composed Of Silk Fibroin-Polypyrrole Film, Xiaoteng Jia, Caiyun Wang, Chen Zhao, Yu Ge, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Biodegradable active implantable devices can be used to diagnose and/or treat disease and eventually disappear without surgical removal. If an "external" energy source is required for effective operation then a biocompatible and biodegradable battery would be ideal. In this study, a partially biodegradable Mg-air bioelectric battery (biobattery) is demonstrated using a silk fibroin-polypyrrole (SF-PPy) film cathode coupled with bioresorbable Mg alloy anode in phosphate buffered saline (PBS) electrolyte. PPy is chemically coated onto one side of the silk substrate. SF-PPy film shows a conductivity of ≈1.1 S cm−1 and a mild catalytic activity toward oxygen reduction. It degrades in a …


Substituted Ferrocenes And Iodine As Synergistic Thermoelectrochemical Heat Harvesting Redox Couples In Ionic Liquids, E H.B Anari, Mark S. Romano, W X. Teh, J J. Black, E Jiang, Jun Chen, T Q. To, J Panchompoo, Leigh Aldous Jan 2016

Substituted Ferrocenes And Iodine As Synergistic Thermoelectrochemical Heat Harvesting Redox Couples In Ionic Liquids, E H.B Anari, Mark S. Romano, W X. Teh, J J. Black, E Jiang, Jun Chen, T Q. To, J Panchompoo, Leigh Aldous

Australian Institute for Innovative Materials - Papers

2016 The Royal Society of Chemistry. Combining ferrocene and iodine results in enhanced thermoelectrochemical (or thermogalvanic) waste heat harvesting abilities, for both the Seebeck coefficient and the overall power output. All systems displayed a mixture of ferrocene, ferrocenium, iodine and triiodide. The observed enhancement correlates with lower electron-density on the ferrocene; the synergistic improvement observed for mixtures of substituted ferrocenes and iodine is attributed to the formation of charge-transfer complexes. Combining dibutanoylferrocene and iodine resulted in the highest Seebeck coefficient of 1.67 mV K-1.


Direct Measurements Of Field-Dependent Ordering In A Low-Field Vortex Glass State, Frederick Wells, Alexey V. Pan, X Renshaw Wang, Igor A. Golovchanskiy, Sergey Fedoseev, Hans Hilgenkamp, Anatoly B. Rosenfeld Jan 2016

Direct Measurements Of Field-Dependent Ordering In A Low-Field Vortex Glass State, Frederick Wells, Alexey V. Pan, X Renshaw Wang, Igor A. Golovchanskiy, Sergey Fedoseev, Hans Hilgenkamp, Anatoly B. Rosenfeld

Australian Institute for Innovative Materials - Papers

The variation of topological defect density and hexatic order parameter were measured over a range of micro-Tesla fields in a 2-D superconducting vortex glass. This was achieved through scanning SQUID microscopy of the vortex distribution in YBa2Cu3O7−δ thin films under field-cooled conditions. It was discovered that, although the defect density decreased for increasing magnetic fields, giving the impression of a more lattice-like vortex distribution, the hexatic order parameter also decreased, showing that the distribution was less orientationally ordered.


Indirect-Direct Band Transformation Of Few-Layer Biocl Under Biaxial Strain, Zhongfei Xu, Weichang Hao, Qianfan Zhang, Zhongheng Fu, Haifeng Feng, Yi Du, S X. Dou Jan 2016

Indirect-Direct Band Transformation Of Few-Layer Biocl Under Biaxial Strain, Zhongfei Xu, Weichang Hao, Qianfan Zhang, Zhongheng Fu, Haifeng Feng, Yi Du, S X. Dou

Australian Institute for Innovative Materials - Papers

Being a new two-dimensional layered compounds, the tunable indirect-direct band transformation of BiOCl with different layers can be realized by introducing the biaxial tensile or compressive strains. The band structure and stability of BiOCl with different layers are first researched to clarify the influence of layer numbers. A phase transformation of bilayer BiOCl and metallic characteristic for all are observed under large tensile and compressive strains, respectively. In addition, bond length, interlayer spacing, and band decomposed charge density are calculated to analyze the mechanism behind these phenomena. The results indicate that the band structure transformation is primarily related to the …


Vibration Effect On Magnetization And Critical Current Density Of Superconductors, Igor A. Golovchanskiy, Alexey V. Pan, Jonathan George, Frederick Wells, Sergey Fedoseev, Anatoly B. Rosenfeld Jan 2016

Vibration Effect On Magnetization And Critical Current Density Of Superconductors, Igor A. Golovchanskiy, Alexey V. Pan, Jonathan George, Frederick Wells, Sergey Fedoseev, Anatoly B. Rosenfeld

Australian Institute for Innovative Materials - Papers

In this work the effect of vibrations on critical current density ( Jc) of superconductors has been studied. The vibrations are shown to affect Jc of all types of superconductors during their measurements, employing a vibrating sample magnetometer (VSM). Increasing vibration frequency ( f ) and/or amplitude (A) leads to progressive reduction of Jc as a function of magnetic field (Ba). The effect of vibrations is substantially stronger in thin films. It leads to development of unexpected kinks on Jc (Ba) curves. Analysis of magnetization loops and relaxation of magnetization in YBCO films revealed that the vibration effect can be …


The Magneto-Structural Transition In Mn1-Xfexcoge, Qing Yon Ren, Wayne D. Hutchison, Jian Li Wang, Andrew J. Studer, M F. Md Din, S Munoz Perez, John M. Cadogan, Stewart J. Campbell Jan 2016

The Magneto-Structural Transition In Mn1-Xfexcoge, Qing Yon Ren, Wayne D. Hutchison, Jian Li Wang, Andrew J. Studer, M F. Md Din, S Munoz Perez, John M. Cadogan, Stewart J. Campbell

Australian Institute for Innovative Materials - Papers

Large refrigeration capacities, between 212(30) J kg-1 and 261(40) J kg-1 for a magnetic field change from 0 T to 5 T, were obtained in Mn1-xFexCoGe (x = 0.01, 0.02, 0.03 and 0.04) compounds. A partial magnetic phase diagram has been derived on the basis of magnetic transition and martensitic transformation temperatures determined from differential scanning calorimetry (200 K to 450 K), variable temperature x-ray diffraction (20 K to 310 K) and magnetisation measurements (5 K to 340 K; 0.01 T). Mn1-xFexCoGe compounds with compositions in the range x = 0.01 to 0.03 exhibit magneto-structural transitions. Neutron diffraction experiments were …


Electrochemically Active, Novel Layered M-Znv2o6 Nanobelts For Highly Rechargeable Na-Ion Energy Storage, Yan Sun, Chun-Sheng Li, Qiuran Yang, Shulei Chou, Hua-Kun Liu Jan 2016

Electrochemically Active, Novel Layered M-Znv2o6 Nanobelts For Highly Rechargeable Na-Ion Energy Storage, Yan Sun, Chun-Sheng Li, Qiuran Yang, Shulei Chou, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Electrode materials with a three-dimensional (3D) layered framework and excellent electrochemical stability can provide a new avenue for enhancing the overall performance of promising sodium ion batteries. Here, we show that layered monoclinic (m) - ZnV2O6 nanobelts with high chemical activity for Na-ion energy storage have been effectively fabricated via a rapid microwave irradiation method over the reaction time of 8 h, in which the fabricating efficiency is 24.5 times greater in comparison with the traditional hydrothermal method. The morphology and phase evolutions were verified by means of X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. This study also …


Characterisation Of Graphene Fibres And Graphene Coated Fibres Using Capacitively Coupled Contactless Conductivity Detector, Joan M. Cabot, Emer Duffy, Sinead Currivan, Andres Ruland Palaia, Rouhollah Jalili, Attila J. Mozer, Peter C. Innis, Gordon G. Wallace, Michael C. Breadmore, Brett Paull Jan 2016

Characterisation Of Graphene Fibres And Graphene Coated Fibres Using Capacitively Coupled Contactless Conductivity Detector, Joan M. Cabot, Emer Duffy, Sinead Currivan, Andres Ruland Palaia, Rouhollah Jalili, Attila J. Mozer, Peter C. Innis, Gordon G. Wallace, Michael C. Breadmore, Brett Paull

Australian Institute for Innovative Materials - Papers

The use of capacitively coupled contactless conductivity detection (C 4 D) for the characterisation of thin conductive graphene fi bres, graphene composite fi bres, and graphene coated fi brous materials is demon- strated for the fi rst time. Within a few seconds, the non-destructive C 4 D detector provides a pro fi le of the longetudinal physical homogeneity of the fi bre, as well as extra information regarding fi bre mophology and composition. In addition to the theoretical considerations related to the factors a ff ect the output signal, this work evaluates the properties of graphene fi bres using scanning …


Systematic Elongation Of Thienyl Linkers And Their Effect On Optical And Electrochemical Properties In Carbazole-Bodipy Donor-Acceptor Systems, Alina Brzeczek, Katarzyna Piwowar, Wojciech Domagala, Mikotaj M. Mikotajczyk, Krzysztof Walczak, Pawel W. Wagner Jan 2016

Systematic Elongation Of Thienyl Linkers And Their Effect On Optical And Electrochemical Properties In Carbazole-Bodipy Donor-Acceptor Systems, Alina Brzeczek, Katarzyna Piwowar, Wojciech Domagala, Mikotaj M. Mikotajczyk, Krzysztof Walczak, Pawel W. Wagner

Australian Institute for Innovative Materials - Papers

Synthesis, spectral and electrochemical properties of a series of new panchromatic BODIPY donor-acceptor-donor derivatives, comprising carbazole conjugated with systematically elongated framework by thiophene-based linkers were investigated. It has been found that elongation of the π-system with one thiophene unit shifts the spectra toward near infrared, while incorporation of next thiophene derivatives has only limited influence on the lowest energy transition, causing no further shift of absorption maxima. Elongation of π-conjugation of the donor arm tunes the electron properties, influencing the ionization potential (IP) and electron affinity (EA) values of the molecules. The experimental results are supported by quantum chemical computations …


Elemental Distributions Within Multiphase Quaternary Pb Chalcogenide Thermoelectric Materials Determined Through Three-Dimensional Atom Probe Tomography, Sima Aminorroaya-Yamini, Tong Li, David R. G Mitchell, Julie M. Cairney Jan 2016

Elemental Distributions Within Multiphase Quaternary Pb Chalcogenide Thermoelectric Materials Determined Through Three-Dimensional Atom Probe Tomography, Sima Aminorroaya-Yamini, Tong Li, David R. G Mitchell, Julie M. Cairney

Australian Institute for Innovative Materials - Papers

Nanostructured multiphase p-type lead chalcogenides have shown the highest efficiencies amongst thermoelectric materials. However, their electronic transport properties have been described assuming homogenous distribution of dopants between phases. Here, we have analyzed elemental distributions in precipitates and matrices of nanostructured multiphase quaternary Pb chalcogenides doped to levels below and above the solubility limit of the matrix, using three-dimensional atom probe tomography. We demonstrate that partitioning of sodium and selenium occur between the matrix and secondary phase in both lightly- and heavily-doped compounds and that the concentrations of sodium and selenium in precipitates are higher than those in the matrices. This …


Tuning The Morphology Of Co3o4 On Ni Foam For Supercapacitor Application, Zheyin Yu, Zhenxiang Cheng, Zhixin Tai, Xiaolin Wang, Chandrasekar Mayandi Subramaniyam, Chunsheng Fang, Shaymaa Al-Rubaye, Xiaotian Wang, S X. Dou Jan 2016

Tuning The Morphology Of Co3o4 On Ni Foam For Supercapacitor Application, Zheyin Yu, Zhenxiang Cheng, Zhixin Tai, Xiaolin Wang, Chandrasekar Mayandi Subramaniyam, Chunsheng Fang, Shaymaa Al-Rubaye, Xiaotian Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

In this work, NH4F was used as a vital additive to control the morphology of Co3O4 precursors on Ni foam in a conventional hydrothermal reaction, and then, via thermal decomposition, to obtain Co3O4 material. The amount of NH4F plays a pivotal role in the formed morphology of the Co3O4 precursors, and four morphologies of Co3O4 were obtained through close control of the amount of additive: nanowires, thin nanowire-clusters, thick nanowire-clusters, and fan-like bulks. The morphological evolution process of the Co3O4 precursors has been investigated according to their intermediates at different reaction stages, and some novel growth mechanisms are proposed: (1) …


Lead-Free Snte-Based Thermoelectrics: Enhancement Of Thermoelectric Performance By Doping With Gd/Ag, Lijuan Zhang, Jian Li Wang, Zhenxiang Cheng, Qiao Sun, Zhen Li, S X. Dou Jan 2016

Lead-Free Snte-Based Thermoelectrics: Enhancement Of Thermoelectric Performance By Doping With Gd/Ag, Lijuan Zhang, Jian Li Wang, Zhenxiang Cheng, Qiao Sun, Zhen Li, S X. Dou

Australian Institute for Innovative Materials - Papers

SnTe, with the same rock-salt structure as PbTe, is a potentially attractive thermoelectric material. Pristine SnTe has poor thermoelectric performance because of its very high hole concentration resulting from intrinsic Sn vacancies, which leads to a high thermal conductivity and a low Seebeck coefficient. In this work, the thermoelectric properties of SnTe were modified by doping with different contents of gadolinium and silver. It is found that SnTe doped with optimal gadolinium (i.e. Gd0.06Sn0.94Te) exhibited extraordinarily low lattice thermal conductivity that is close to the theoretical minimum. The drastic reduction of lattice thermal conductivity is attributed to the formation of …


Improved Cycling Stability Of Lithium-Sulphur Batteries By Enhancing The Retention Of Active Material With A Sandwiched Hydrothermally Treated Graphite Film, Yuede Pan, Shulei Chou, Hua-Kun Liu, S X. Dou Jan 2016

Improved Cycling Stability Of Lithium-Sulphur Batteries By Enhancing The Retention Of Active Material With A Sandwiched Hydrothermally Treated Graphite Film, Yuede Pan, Shulei Chou, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

A new lithium-sulphur battery with a hydrothermally treated graphite film sandwiched between the separator and the sulphur cathode shows increased capacity, enhanced cycling stability and improved coulombic efficiency. After 50 cycles, a high capacity of 631 mA h g-1 is maintained, compared to 203 mA h g-1 for the Li-S battery with conventional configuration. Moreover, the coulombic efficiency is increased to near 100% from around 94%. This improved electrochemical performance could be attributed to the new cell configuration, because the graphite film greatly retains the active material by alleviating the polysulphide shuttling problem and providing extra reaction sites for sulphur …


Binder-Free And Carbon-Free 3d Porous Air Electrode For Li-O2 Batteries With High Efficiency, High Capacity, And Long Life, Wenbin Luo, Xuanwen Gao, Dongqi Shi, Shulei Chou, Jiazhao Wang, Hua-Kun Liu Jan 2016

Binder-Free And Carbon-Free 3d Porous Air Electrode For Li-O2 Batteries With High Efficiency, High Capacity, And Long Life, Wenbin Luo, Xuanwen Gao, Dongqi Shi, Shulei Chou, Jiazhao Wang, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Pt-Gd alloy polycrystalline thin film is deposited on 3D nickel foam by pulsed laser deposition method serving as a whole binder/carbon-free air electrode, showing great catalytic activity enhancement as an efficient bifunctional catalyst for the oxygen reduction and evolution reactions in lithium oxygen batteries. The porous structure can facilitate rapid O2 and electrolyte diffusion, as well as forming a continuous conductive network throughout the whole energy conversion process. It shows a favorable cycle performance in the full discharge/charge model, owing to the high catalytic activity of the Pt-Gd alloy composite and 3D porous nickel foam structure. Specially, excellent cycling performance …


Host Structural Stabilization Of Li1.232mn0.615ni0.154o2 Through K-Doping Attempt: Toward Superior Electrochemical Performances, Zhuo Zheng, Xiao Dong Guo, Yan Jun Zhong, Wei-Bo Hua, Chong-Heng Shen, Shulei Chou, Xiu-Shan Yang Jan 2016

Host Structural Stabilization Of Li1.232mn0.615ni0.154o2 Through K-Doping Attempt: Toward Superior Electrochemical Performances, Zhuo Zheng, Xiao Dong Guo, Yan Jun Zhong, Wei-Bo Hua, Chong-Heng Shen, Shulei Chou, Xiu-Shan Yang

Australian Institute for Innovative Materials - Papers

Lithium-rich layered cathodes are known famously for its superior capacity over traditional layered oxides but trapped for lower initial coulombic efficiency, poorer rate capability and worse cyclic stability in spite of diverse attempts. Herein, a new K-stabilized Li-rich layered cathode synthesized through a simple oxalate co-precipitation is reported for its super electrochemical performances. Compared with pristine Li-rich layered cathode, K-stabilized one reaches a higher initial coulombic efficiency of 87% from 76% and outruns for 94% of capacity retention and 244 mAh g-1 of discharge capacity at 0.5C after 100 cycles. Moreover, 133 mAh g-1 of discharge capacity can be delivered …


Aqueous Electrosynthesis Of An Electrochromic Material Based Water-Soluble Edot-Menh2 Hydrochloride, Hui Sun, Long Zhang, Liqi Dong, Xiaofei Zhu, Shouli Ming, Youshan Zhang, Huakun Xing, Xuemin Duan, Jingkun Xu Jan 2016

Aqueous Electrosynthesis Of An Electrochromic Material Based Water-Soluble Edot-Menh2 Hydrochloride, Hui Sun, Long Zhang, Liqi Dong, Xiaofei Zhu, Shouli Ming, Youshan Zhang, Huakun Xing, Xuemin Duan, Jingkun Xu

Australian Institute for Innovative Materials - Papers

2'-Aminomethyl-3,4-ethylenedioxythiophene (EDOT-MeNH2) showed unsatisfactory results when its polymerization occurred in organic solvent in our previous report. Therefore, a water-soluble EDOT derivative was designed by using hydrochloric modified EDOT-MeNH2 (EDOT-MeNH2·HCl) and electropolymerized in aqueous solution to form the corresponding polymer with excellent electrochromic properties. Moreover, the polymer was systematically explored, including electrochemical, optical properties and structure characterization. Cyclic voltammetry showed low oxidation potential of EDOT-MeNH2·HCl (0.85 V) in aqueous solution, leading to the facile electrodeposition of uniform the polymer film with outstanding electroactivity. Compared with poly(2′-aminomethyl- 3,4-ethylenedioxythiophene) (PEDOT-MeNH2), poly(2′-aminomethyl-3,4-ethylenedioxythiophene salt) (PEDOT-MeNH3 +A-) revealed higher efficiencies (156 cm2 C-1), lower bandgap (1.68 …


A Green And Facile Way To Prepare Granadilla-Like Silicon-Based Anode Materials For Li-Ion Batteries, Lei Zhang, Ranjusha Rajagopalan, Haipeng Guo, Xianluo Hu, S X. Dou, Hua-Kun Liu Jan 2016

A Green And Facile Way To Prepare Granadilla-Like Silicon-Based Anode Materials For Li-Ion Batteries, Lei Zhang, Ranjusha Rajagopalan, Haipeng Guo, Xianluo Hu, S X. Dou, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

A yolk-shell-structured carbon@void@silicon (CVS) anode material in which a void space is created between the inside silicon nanoparticle and the outer carbon shell is considered as a promising candidate for Li-ion cells. Untill now, all the previous yolk-shell composites were fabricated through a templating method, wherein the SiO2 layer acts as a sacrificial layer and creates a void by a selective etching method using toxic hydrofluoric acid. However, this method is complex and toxic. Here, a green and facile synthesis of granadilla-like outer carbon coating encapsulated silicon/carbon microspheres which are composed of interconnected carbon framework supported CVS nanobeads is reported. …


Enhancement Of Dye Regeneration Kinetics In Dichromophoric Porphyrin-Carbazole Triphenylamine Dyes Influenced By More Exposed Radical Cation Orbitals, Long Zhao, Pawel W. Wagner, Jonathan E. Barnsley, Tracey M. Clarke, Keith C. Gordon, Shogo Mori, Attila J. Mozer Jan 2016

Enhancement Of Dye Regeneration Kinetics In Dichromophoric Porphyrin-Carbazole Triphenylamine Dyes Influenced By More Exposed Radical Cation Orbitals, Long Zhao, Pawel W. Wagner, Jonathan E. Barnsley, Tracey M. Clarke, Keith C. Gordon, Shogo Mori, Attila J. Mozer

Australian Institute for Innovative Materials - Papers

Reduction kinetics of oxidized dyes absorbed on semiconductor surfaces and immersed in redox active electrolytes has been mainly modeled based on the free energy difference between the oxidation potential of the dye and the redox potential of the electrolyte. Only a few mechanisms have been demonstrated to enhance the kinetics by other means. In this work, the rate constant of the reduction of oxidized porphyrin dye is enhanced by attaching non-conjugated carbazole triphenylamine moiety using iodine/triiodide and tris(2,2′-bispyridinium)cobalt II/III electrolytes. These results are obtained using transient absorption spectroscopy by selectively probing the regeneration kinetics at the porphyrin radical cation and …