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Selected Works

2014

Materials

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

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

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

Shi Xue Dou

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 …


Organic Bionics: Molecules, Materials And Medical Devices, Gordon G. Wallace, Simon E. Moulton Mar 2014

Organic Bionics: Molecules, Materials And Medical Devices, Gordon G. Wallace, Simon E. Moulton

Gordon Wallace

The uses of bionic devices that can improve the quality of human life are presented. Significant among them are the bionic ear or the bionic eye which has helped to regain use of important sensory organs. Bionics is the use of a biological entity and electronic devices that are put together to create the required implant.


Facile Synthesis Of Reduced Graphene Oxide/Mwnts Nanocomposite Supercapacitor Materials Tested As Electrophoretically Deposited Films On Glassy Carbon Electrodes, Widsanusan Chartarrayawadee, Simon E. Moulton, Chee O. Too, Byung C. Kim, Rao Yepuri, Anthony C. Romeo, Gordon G. Wallace Mar 2014

Facile Synthesis Of Reduced Graphene Oxide/Mwnts Nanocomposite Supercapacitor Materials Tested As Electrophoretically Deposited Films On Glassy Carbon Electrodes, Widsanusan Chartarrayawadee, Simon E. Moulton, Chee O. Too, Byung C. Kim, Rao Yepuri, Anthony C. Romeo, Gordon G. Wallace

Gordon Wallace

This paper reports on a facile synthesis method for reduced graphene oxide (rGO)/multi-walled carbon nanotubes (MWNTs) nanocomposites. The initial step involves the use of graphene oxide to disperse the MWNTs, with subsequent reduction of the resultant graphene oxide/MWNTs composites using l-ascorbic acid (LAA) as a mild reductant. Reduction by LAA preserves the interaction between the rGO sheets and MWNTs. The dispersion-containing rGO/MWNTs composites was characterized and electrophoretically deposited anodically onto glassy carbon electrodes to form high surface area films for capacitance testing. Pseudo capacitance peaks were observed in the rGO/MWNTs composite electrodes, resulting in superior performance with capacitance values up …


Nanocomposites Of Silicon And Carbon Derived From Coal Tar Pitch: Cheap Anode Materials For Lithium-Ion Batteries With Long Cycle Life And Enhanced Capacity, Yun-Xiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou Mar 2014

Nanocomposites Of Silicon And Carbon Derived From Coal Tar Pitch: Cheap Anode Materials For Lithium-Ion Batteries With Long Cycle Life And Enhanced Capacity, Yun-Xiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou

Shi Xue Dou

From energy and environmental consideration, an industrial waste product, coal tar pitch (CTP), is used as the carbon source for Si/AC composite. We exploited a facile sintering method to largely scale up Si/amorphous carbon nanocomposite. The composites with 20 wt.% silicon with PVdF binder exhibited stable lithium storage ability for prolonged cycling. The composite anode delivered a capacity of 400.3 mAh g−1 with a high capacity retention of 71.3% after 1000 cycles. Various methods are used to investigate the reason for the outstanding cyclability. The results indicate that the silicon nanoparticles are wrapped by amorphous SiOx and AC in Si/AC …


Formation Of Magnesium Diboride-Based Materials With High Critical Currents And Mechanical Characteristics By High-Pressure Synthesis, Tetiana Prikhna, W. Gawalek, Ya M. Savchuk, N. V. Sergienko, V. E. Moshchil, M. Wendt, M. Zeisberger, T. Habisreuther, V. B. Sverdun, S X. Dou, S. N. Dub, V. S. Melnikov, Ch Schmidt, J. Dellith, P. A. Nagorny Mar 2014

Formation Of Magnesium Diboride-Based Materials With High Critical Currents And Mechanical Characteristics By High-Pressure Synthesis, Tetiana Prikhna, W. Gawalek, Ya M. Savchuk, N. V. Sergienko, V. E. Moshchil, M. Wendt, M. Zeisberger, T. Habisreuther, V. B. Sverdun, S X. Dou, S. N. Dub, V. S. Melnikov, Ch Schmidt, J. Dellith, P. A. Nagorny

Shi Xue Dou

The developed method of high-pressure synthesis (HPS) allows producing nanostructural highly dense material based on MGB2, which possesses the highest superconducting and mechanical characteristics among the known world analogues, in the form of blocks that are suitable for application in SC electromotors and pumps. Additions of Zr can increase critical current density (jc) of synthesized at 2 GPa and 750-800 °C MGB2 in the same manner as additions of Ta or Ti, i.e. due to the absorption of impurity hydrogen forming the ZrH2. The formation of ZrB2 phase at higher synthesis temperatures (about 950 °C) in HPS MGB2 does not …