The orientation construction of S-doped porous carbon fibers(SPCFs)is realized by the facile template-directed methodology using asphalt powder as carbon source.The unique fiber-like morphology without destruction can...The orientation construction of S-doped porous carbon fibers(SPCFs)is realized by the facile template-directed methodology using asphalt powder as carbon source.The unique fiber-like morphology without destruction can be well duplicated from the template by the developed methodology.MgSO4 fibers serve as both templates and S dopant,realizing the in-situ S doping into carbon frameworks.The effects of different reaction temperatures on the yield and S doping level of SPCFs are investigated.The S doping can not only significantly enhance the electrical conductivity,but also introduce more defects or disorders.As anode material for lithium ion batteries(LIBs),SPCFs electrode delivers better rate capability than undoped PCFs.And the capacity of SPCFs electrode retains around 90%after 300 cycles at 2 A g1,exhibiting good cycling stability.As the electrocatalysts for fuel cells,the onset potentials of SPCFs obtained at 800 and 900C are concentrated at 0.863 V,and the higher kinetic current densities at 0.4 V of them are larger than that of PCFs,demonstrating the superior electrocatalytic performance.Due to the synergistic effect of abundant pore channels and S doping,SPCFs electrode exhibits superior electrochemical performances as anode for LIBs and elecctrocatalyst for fuel cells,respectively.Additionally,the oriented conversion of asphalt powder into high-performance electrode material in this work provides a new way for the high value application of asphalt.展开更多
Fuel cells using borohydride as the fuel have received much attention because of high energy density and theoretical working potential.In this work,LaNi4.5Al0.5 hydrogen storage alloy used as the anodic material has b...Fuel cells using borohydride as the fuel have received much attention because of high energy density and theoretical working potential.In this work,LaNi4.5Al0.5 hydrogen storage alloy used as the anodic material has been investigated.It was found that the increasing operation temperature was helpful to the open-circuit potential,the discharge potential and the power density,but showed a negative effect on the utilization of the fuel due to the accelerated hydrogen evolution.The high KOH concentration was favorable for high-rate discharge capability.The adsorption and transformation of hydrogen on LaNi4.5Al0.5 alloy electrode has been observed,but its contribution to the discharge capability during a high-rate discharge was small.展开更多
文摘The orientation construction of S-doped porous carbon fibers(SPCFs)is realized by the facile template-directed methodology using asphalt powder as carbon source.The unique fiber-like morphology without destruction can be well duplicated from the template by the developed methodology.MgSO4 fibers serve as both templates and S dopant,realizing the in-situ S doping into carbon frameworks.The effects of different reaction temperatures on the yield and S doping level of SPCFs are investigated.The S doping can not only significantly enhance the electrical conductivity,but also introduce more defects or disorders.As anode material for lithium ion batteries(LIBs),SPCFs electrode delivers better rate capability than undoped PCFs.And the capacity of SPCFs electrode retains around 90%after 300 cycles at 2 A g1,exhibiting good cycling stability.As the electrocatalysts for fuel cells,the onset potentials of SPCFs obtained at 800 and 900C are concentrated at 0.863 V,and the higher kinetic current densities at 0.4 V of them are larger than that of PCFs,demonstrating the superior electrocatalytic performance.Due to the synergistic effect of abundant pore channels and S doping,SPCFs electrode exhibits superior electrochemical performances as anode for LIBs and elecctrocatalyst for fuel cells,respectively.Additionally,the oriented conversion of asphalt powder into high-performance electrode material in this work provides a new way for the high value application of asphalt.
基金supported by the Zhejiang Natural Science Foundation (Nos. Y405496 and 2008C14040)the National Fundamental Research "973" Prophase Project (2007CB216409)
文摘Fuel cells using borohydride as the fuel have received much attention because of high energy density and theoretical working potential.In this work,LaNi4.5Al0.5 hydrogen storage alloy used as the anodic material has been investigated.It was found that the increasing operation temperature was helpful to the open-circuit potential,the discharge potential and the power density,but showed a negative effect on the utilization of the fuel due to the accelerated hydrogen evolution.The high KOH concentration was favorable for high-rate discharge capability.The adsorption and transformation of hydrogen on LaNi4.5Al0.5 alloy electrode has been observed,but its contribution to the discharge capability during a high-rate discharge was small.
