The conversion reaction-based anode materials of sodium ion batteries have relatively high capacity;however,the application of these materials is limited by their structural collapse due to the poor structure stabilit...The conversion reaction-based anode materials of sodium ion batteries have relatively high capacity;however,the application of these materials is limited by their structural collapse due to the poor structure stability.In this work,MoSe_(2) nanosheets were synthesized by a solvothermal method.An organic solvent was intercalated into the MoSe_(2) materials to enlarge the interlayer spacing and improve the conductivity of the material.The MoSe_(2) material was coated with an organic pyrolysis carbon and then a uniform carbon layer was formed.The surface carbon hybridization of the nanosheet materials was realized by the introduction of heteroatoms during the sintering process.The as-prepared MoSe_(2)@N,P-C composites showed a superior rate performance as it could maintain the integrity of the morphology and structure under a high current density.The composites had a discharge specific capacity of 302.4 mA·h/g after 100 cycles at 0.5 A/g,and the capacity retention rate was 84.96%.展开更多
A series of porous carbon materials with wide range of specific surface areas and different heteroatom contents had been prepared using polyaniline as carbon precursor and KOH as an activating agent. Effect of surface...A series of porous carbon materials with wide range of specific surface areas and different heteroatom contents had been prepared using polyaniline as carbon precursor and KOH as an activating agent. Effect of surface area and heteroatom of porous carbon materials on specific capacitance was investigated thoroughly in two typical aqueous KOH and organic 1-butyl-3- methylimidazolium tetrafluoroborate/acetonitirle electrolytes. The different trends of capacitance performance were observed in these two electrolytes. Electrochemical analyses suggested that the presence of faradaic interactions on heteroatom-enriched carbon materials in organic environment is less significant than that observed in aqueous electrolytes. Thus, in aqueous electrolyte, a balance between surface area and heteroatom content of activated porous carbon would be found to develop a supercapacitor with high energy density. In organic electrolyte, the capacitance performance of porous carbon is strongly dependent on the surface area. The results may be useful for the design of porous carbon-based supercapacitor with the desired capacitive performance in aqueous and organic electrolytes.展开更多
基金Project(51572300) supported by the National Natural Science Foundation of China。
文摘The conversion reaction-based anode materials of sodium ion batteries have relatively high capacity;however,the application of these materials is limited by their structural collapse due to the poor structure stability.In this work,MoSe_(2) nanosheets were synthesized by a solvothermal method.An organic solvent was intercalated into the MoSe_(2) materials to enlarge the interlayer spacing and improve the conductivity of the material.The MoSe_(2) material was coated with an organic pyrolysis carbon and then a uniform carbon layer was formed.The surface carbon hybridization of the nanosheet materials was realized by the introduction of heteroatoms during the sintering process.The as-prepared MoSe_(2)@N,P-C composites showed a superior rate performance as it could maintain the integrity of the morphology and structure under a high current density.The composites had a discharge specific capacity of 302.4 mA·h/g after 100 cycles at 0.5 A/g,and the capacity retention rate was 84.96%.
基金supported by the Top Hundred Talents Program of Chinese Academy of Sciencesthe National Natural Science Foundation of China(21203223)the Youth Science Foundation of Gansu Province(1107RJYA274)
文摘A series of porous carbon materials with wide range of specific surface areas and different heteroatom contents had been prepared using polyaniline as carbon precursor and KOH as an activating agent. Effect of surface area and heteroatom of porous carbon materials on specific capacitance was investigated thoroughly in two typical aqueous KOH and organic 1-butyl-3- methylimidazolium tetrafluoroborate/acetonitirle electrolytes. The different trends of capacitance performance were observed in these two electrolytes. Electrochemical analyses suggested that the presence of faradaic interactions on heteroatom-enriched carbon materials in organic environment is less significant than that observed in aqueous electrolytes. Thus, in aqueous electrolyte, a balance between surface area and heteroatom content of activated porous carbon would be found to develop a supercapacitor with high energy density. In organic electrolyte, the capacitance performance of porous carbon is strongly dependent on the surface area. The results may be useful for the design of porous carbon-based supercapacitor with the desired capacitive performance in aqueous and organic electrolytes.
