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Articles 1 - 14 of 14
Full-Text Articles in Physical Sciences and Mathematics
Effect Of Tensile Load On The Actuation Performance Of Ph-Sensitive Hydrogels, Sina Naficy, Geoffrey M. Spinks
Effect Of Tensile Load On The Actuation Performance Of Ph-Sensitive Hydrogels, Sina Naficy, Geoffrey M. Spinks
Australian Institute for Innovative Materials - Papers
pH-responsive hydrogels are capable of converting chemical energy to mechanical work. To optimize their use as actuators, their response when operating against an external load must be fully characterized. Here, the actuation strain of a model pH-sensitive hydrogel as a function of different constant loads is studied. The experimental actuation strain, produced by switching the pH from 2 to 12, decreases significantly and monotonically with increasing initial tensile load. Two models are developed to predict the actuation strain as a function of applied stress. Simple mechanical models based on the change in hydrogel modulus and cross sectional area due to …
Facile Method To Synthesize Na-Enriched Na1+Xfefe(Cn)6 Frameworks As Cathode With Superior Electrochemical Performance For Sodium-Ion Batteries, Weijie Li, Shulei Chou, Jiazhao Wang, Yong-Mook Kang, Jianli Wang, Yong Liu, Qinfen Gu, Hua-Kun Liu, S X. Dou
Facile Method To Synthesize Na-Enriched Na1+Xfefe(Cn)6 Frameworks As Cathode With Superior Electrochemical Performance For Sodium-Ion Batteries, Weijie Li, Shulei Chou, Jiazhao Wang, Yong-Mook Kang, Jianli Wang, Yong Liu, Qinfen Gu, Hua-Kun Liu, S X. Dou
Australian Institute for Innovative Materials - Papers
Different Na-enriched Na1+xFeFe(CN)6 samples can be synthesized by a facile one-step method, utilizing Na4Fe(CN)6 as the precursor in a different concentration of NaCl solution. As-prepared samples were characterized by a combination of synchrotron X-ray powder diffraction (S-XRD), Mössbauer spectroscopy, Raman spectroscopy, magnetic measurements, thermogravimetric analysis, X-ray photoelectron spectroscopy, and inductively coupled plasma analysis. The electrochemical results show that the Na1.56Fe[Fe(CN)6]·3.1H2O (PB-5) sample shows a high specific capacity of more than 100 mAh g-1 and excellent capacity retention of 97% over 400 cycles. The details structural evolution during …
Dual Yolk-Shell Structure Of Carbon And Silica-Coated Silicon For High-Performance Lithium-Ion Batteries, L Y. Yang, H Z. Li, Jun Liu, Ziqi Sun, S S. Tang, M Lei
Dual Yolk-Shell Structure Of Carbon And Silica-Coated Silicon For High-Performance Lithium-Ion Batteries, L Y. Yang, H Z. Li, Jun Liu, Ziqi Sun, S S. Tang, M Lei
Australian Institute for Innovative Materials - Papers
Silicon batteries have attracted much attention in recent years due to their high theoretical capacity, although a rapid capacity fade is normally observed, attributed mainly to volume expansion during lithiation. Here, we report for the first time successful synthesis of Si/void/SiO2/void/C nanostructures. The synthesis strategy only involves selective etching of SiO2 in Si/SiO2/C structures with hydrofluoric acid solution. Compared with reported results, such novel structures include a hard SiO2-coated layer, a conductive carbon-coated layer, and two internal void spaces. In the structures, the carbon can enhance conductivity, the SiO2 layer has mechanically …
Effective Enhancement Of The Electrochemical Performance Of Layered Cathode Li1.5mn0.75ni0.25o2.5 Via A Novel Facile Molten Salt Method, Zhuo Zheng, Wei-Bo Hua, S Liao, Yan Jun Zhong, En-Hui Wang, Bin-Bin Xu, Hua-Kun Liu, Ben-He Zhong
Effective Enhancement Of The Electrochemical Performance Of Layered Cathode Li1.5mn0.75ni0.25o2.5 Via A Novel Facile Molten Salt Method, Zhuo Zheng, Wei-Bo Hua, S Liao, Yan Jun Zhong, En-Hui Wang, Bin-Bin Xu, Hua-Kun Liu, Ben-He Zhong
Australian Institute for Innovative Materials - Papers
A series of nanocrystalline lithium-rich cathode materials Li1.5Mn0.75Ni0.25O2.5 have been prepared by a novel synthetic process, which combines the co-precipitation method and a modified molten salt method. By using a moderate excess of 0.5LiNO3-0.5LiOH eutectic salts as molten media and reactants, the usage of deionized water or alcohol in the subsequent wash process is successfully reduced, compared with the traditional molten salt method. The materials with different excess Li salt content, Li/M (M = Ni + Mn) = 1.55, 1.65, 1.75, 1.85, 1.95, 2.05, molar ratio, show distinct differences in their …
Increased Upconversion Performance For Thin Film Solar Cells: A Trimolecular Composition, Yuen Yap Cheng, Andrew Nattestad, Tim F. Schulze, Rowan W. Macqueen, Burkhard Fückel, Klaus Lips, Gordon G. Wallace, Tony Khoury, Maxwell J. Crossley, Timothy W. Schmidt
Increased Upconversion Performance For Thin Film Solar Cells: A Trimolecular Composition, Yuen Yap Cheng, Andrew Nattestad, Tim F. Schulze, Rowan W. Macqueen, Burkhard Fückel, Klaus Lips, Gordon G. Wallace, Tony Khoury, Maxwell J. Crossley, Timothy W. Schmidt
Australian Institute for Innovative Materials - Papers
Photochemical upconversion based on triplet-triplet annihilation (TTA-UC) is employed to enhance the short-circuit currents generated by two varieties of thin-film solar cells, a hydrogenated amorphous silicon (a-Si:H) solar cell and a dye-sensitized solar cell (DSC). TTA-UC is exploited to harvest transmitted sub-bandgap photons, combine their energies and re-radiate upconverted photons back towards the solar cells. In the present study we employ a dual-emitter TTA-UC system which allows for significantly improved UC quantum yields as compared to the previously used single-emitter TTA systems. In doing so we achieve record photo-current enhancement values for both the a-Si:H device and the DSC, surpassing …
Synthesis Of Nitrogen-Doped Graphene Via Thermal Treatment Of Graphene Oxide Within Methylimidazole And Its Capacitance Performance As Electric Double Layer Capacitor, Md. Monirul Islam, Shaikh Nayeem Faisal, Anup Kumar Roy, Sonia Ansari, Dean Cardillo, Konstantin K. Konstantinov, Enamul Haque
Synthesis Of Nitrogen-Doped Graphene Via Thermal Treatment Of Graphene Oxide Within Methylimidazole And Its Capacitance Performance As Electric Double Layer Capacitor, Md. Monirul Islam, Shaikh Nayeem Faisal, Anup Kumar Roy, Sonia Ansari, Dean Cardillo, Konstantin K. Konstantinov, Enamul Haque
Australian Institute for Innovative Materials - Papers
Nitrogen-doped graphene was successfully synthesised from graphene oxide (GO) and 2-methylimidazole composite via thermal treatment under argon flow at 700oC within 1h. This synthesised N-doped graphene exhibits homogeneous nitrogen doping with concentration of ~5% in three different nitrogen configuration namelypyridinic N, pyrrolic N and graphitic N. The electric double layer capacitor (EDLC) made up with this N-doped graphene showed excellent specific capacitance 274 F/g at current density of 1A/g, which was ~7 times higher than GO. This EDLC capacitor showed excellent cyclic stability up to 5000 cycles with capacity retention of ~91%.
High-Performance Flexible All-Solid-State Supercapacitor From Large Free-Standing Graphene-Pedot/Pss Films, Yuqing Liu, Bo Weng, Joselito M. Razal, Qun Xu, Chen Zhao, Yuyang Hou, Shayan Seyedin, Rouhollah Jalili, Gordon G. Wallace, Jun Chen
High-Performance Flexible All-Solid-State Supercapacitor From Large Free-Standing Graphene-Pedot/Pss Films, Yuqing Liu, Bo Weng, Joselito M. Razal, Qun Xu, Chen Zhao, Yuyang Hou, Shayan Seyedin, Rouhollah Jalili, Gordon G. Wallace, Jun Chen
Australian Institute for Innovative Materials - Papers
Although great attention has been paid to wearable electronic devices in recent years, flexible lightweight batteries or supercapacitors with high performance are still not readily available due to the limitations of the flexible electrode inventory. In this work, highly flexible, bendable and conductive rGO-PEDOT/PSS films were prepared using a simple bar-coating method. The assembled device using rGO-PEDOT/PSS electrode could be bent and rolled up without any decrease in electrochemical performance. A relatively high areal capacitance of 448 mF cm-2 was achieved at a scan rate of 10 mV s-1 using the composite electrode with a high mass loading (8.49 mg …
A New Strategy For Achieving A High Performance Anode For Lithium Ion Batteries-Encapsulating Germanium Nanoparticles In Carbon Nanoboxes, Dan Li, Hongqiang Wang, Hua-Kun Liu, Zaiping Guo
A New Strategy For Achieving A High Performance Anode For Lithium Ion Batteries-Encapsulating Germanium Nanoparticles In Carbon Nanoboxes, Dan Li, Hongqiang Wang, Hua-Kun Liu, Zaiping Guo
Australian Institute for Innovative Materials - Papers
A novel strategy to improve the electrochemical performance of a germanium anode is proposed via encapsulating germanium nanoparticles in carbon nanoboxes by carbon coating the precursor, germanium dioxide cubes, and then subjecting them to a reduction treatment. The complete and robust carbon boxes are shown to not only provide extra void space for the expansion of germanium nanoparticles after lithium insertion but also offer a large reactive area and reduced distance for the lithium diffusion. Furthermore, the thus-obtained composite, composed of densely stacked carbon nanoboxes encapsulating germanium nanoparticles (germanium at carbon cubes (Ge at CC)), exhibits a high tap density …
Superior Intrinsic Thermoelectric Performance With Zt Of 1.8 In Single-Crystal And Melt-Quenched Highly Dense Cu2-Xse Bulks, Lanling Zhao, Xiaolin Wang, Ji-Yang Wang, Zhenxiang Cheng, S X. Dou, Jun Wang, L Liu
Superior Intrinsic Thermoelectric Performance With Zt Of 1.8 In Single-Crystal And Melt-Quenched Highly Dense Cu2-Xse Bulks, Lanling Zhao, Xiaolin Wang, Ji-Yang Wang, Zhenxiang Cheng, S X. Dou, Jun Wang, L Liu
Australian Institute for Innovative Materials - Papers
Practical applications of the high temperature thermoelectric materials developed so far are partially obstructed by the costly and complicated fabrication process. In this work, we put forward two additional important properties for thermoelectric materials, high crystal symmetry and congruent melting. We propose that the recently discovered thermoelectric material Cu2-xSe, with figure of merit, zT, over 1.5 at T of ~ 1000 K, should meet these requirements, based on our analysis of its crystal structure and the Cu-Se binary phase diagram. We found that its excellent thermoelectric performance is intrinsic, and less dependent on grain size, while highly dense samples can …
Performance Modulation Of Α-Mno2 Nanowires By Crystal Facet Engineering, W Li, Xiangyuan Cui, R Zeng, Guodong Du, Ziqi Sun, Rongkun Zheng, Simon Peter Ringer, S X. Dou
Performance Modulation Of Α-Mno2 Nanowires By Crystal Facet Engineering, W Li, Xiangyuan Cui, R Zeng, Guodong Du, Ziqi Sun, Rongkun Zheng, Simon Peter Ringer, S X. Dou
Australian Institute for Innovative Materials - Papers
Modulation of material physical and chemical properties through selective surface engineering is currently one of the most active research fields, aimed at optimizing functional performance for applications. The activity of exposed crystal planes determines the catalytic, sensory, photocatalytic, and electrochemical behavior of a material. In the research on nanomagnets, it opens up new perspectives in the fields of nanoelectronics, spintronics, and quantum computation. Herein, we demonstrate controllable magnetic modulation of α-MnO2 nanowires, which displayed surface ferromagnetism or antiferromagnetism, depending on the exposed plane. First-principles density functional theory calculations confirm that both Mn- and O-terminated α-MnO2 (1 …
3d Hierarchical Porous Graphene Aerogel With Tunable Meso-Pores On Graphene Nanosheets For High-Performance Energy Storage, Long Ren, K N. Hui, K S. Hui, Yundan Liu, Xiang Qi, Jianxin Zhong, Yi Du, Jianping Yang
3d Hierarchical Porous Graphene Aerogel With Tunable Meso-Pores On Graphene Nanosheets For High-Performance Energy Storage, Long Ren, K N. Hui, K S. Hui, Yundan Liu, Xiang Qi, Jianxin Zhong, Yi Du, Jianping Yang
Australian Institute for Innovative Materials - Papers
New and novel 3D hierarchical porous graphene aerogels (HPGA) with uniform and tunable mesopores (e.g., 21 and 53 nm) on graphene nanosheets (GNS) were prepared by a hydrothermal self-assembly process and an in-situ carbothermal reaction. The size and distribution of the meso-pores on the individual GNS were uniform and could be tuned by controlling the sizes of the Co3O4 NPs used in the hydrothermal reaction. This unique architecture of HPGA prevents the stacking of GNS and promises more electrochemically active sites that enhance the electrochemical storage level significantly. HPGA, as a lithium-ion battery anode, exhibited superior electrochemical performance, including a …
Effects Of Cu Substitution For Sn On The Electrochemical Performance Of La0.7mg0.3al0.3mn0.4sn0.5−Xcuxni3.8 (X = 0-0.5) Alloys For Ni-Mh Batteries, Julio Cesar Serafim Casini, Zaiping Guo, Hua-Kun Liu, Rubens Nunes Faria, Hidetoshi Takiishi
Effects Of Cu Substitution For Sn On The Electrochemical Performance Of La0.7mg0.3al0.3mn0.4sn0.5−Xcuxni3.8 (X = 0-0.5) Alloys For Ni-Mh Batteries, Julio Cesar Serafim Casini, Zaiping Guo, Hua-Kun Liu, Rubens Nunes Faria, Hidetoshi Takiishi
Australian Institute for Innovative Materials - Papers
The effects of substitution of Cu for Sn on the electrochemical discharge capacity performance of La0.7Mg0.3Al0.3Mn0.4Sn0.5−xCuxNi3.8 (x = 0.0, 0.1, 0.2, 0.3, and 0.5) negative electrode alloys were investigated. Results indicate that increasing Cu content enhanced electrochemical behavior by increasing the maximum discharge capacity from 239.8 mA·h/g (x = 0) to 305.2 mA·h/g (x = 0.5), the discharge capacity retention at the 100th cycle from 78.0% (x = 0) to 81.8% (x = 0.5), and the high rate dischargeability (HRD) from 25.7% (x = 0) to 80.6% (x = 0.5).
Research Progress On Design Strategies, Synthesis And Performance Of Limn2o4-Based Cathodes, Fangxin Mao, Wei Dong Guo, Jianmin Ma
Research Progress On Design Strategies, Synthesis And Performance Of Limn2o4-Based Cathodes, Fangxin Mao, Wei Dong Guo, Jianmin Ma
Australian Institute for Innovative Materials - Papers
Spinel LiMn2O4 (LMO)-based composites, due to their combination of low toxicity, abundant natural resources, and excellent electrochemical performance, are regarded as promising candidate cathode materials for lithium ion batteries. Current energy storage demands are not being met with existing materials, however, because of their defects, such as fast capacity fading, low rate capability, and low specific capacity in practical applications. Manganese dissolution during electrochemical processes bears the major responsibility for capacity loss, apart from the electrolyte factor. Low electrical conductivity, low ionic diffusion efficiency, and large structural variation have adverse effects on the electrochemical performance of materials. With respect to …
Role Of Anions On Structure And Pseudocapacitive Performance Of Metal Double Hydroxides Decorated With Nitrogen-Doped Graphene, Nasir Mahmood, Muhammad Nawaz Tahir, Asif Mahmood, Wenlong Yang, Xingxing Gu, Chuanbao Cao, Yawen Zhang, Yanglong Hou
Role Of Anions On Structure And Pseudocapacitive Performance Of Metal Double Hydroxides Decorated With Nitrogen-Doped Graphene, Nasir Mahmood, Muhammad Nawaz Tahir, Asif Mahmood, Wenlong Yang, Xingxing Gu, Chuanbao Cao, Yawen Zhang, Yanglong Hou
Australian Institute for Innovative Materials - Papers
Electrochemical capacitors (EC) bear faster charge-discharge; however, their real applications are still on a long away due to lower capacitance and energy densities which mainly arise from simple surface charge accumulation or/and reaction. Here, a novel synthesis strategy was designed to obtain the purposeful hybrids of nickel cobalt double hydroxide (NiCoDH) with genetic morphology to improve their electrochemical performance as electrode of EC. Nanostructures of metal hydroxides were grown on t he nitrogen-doped graphene (NG) sheets by utilizing defects as nucleation sites and their composition was optimized both by tuning the ratio of Ni:Co as well as the counter halogen …