氟元素掺杂的硅碳复合材料的制备和电化学性能

Preparation and electrochemical performance of F-doped SiO@C composite material

本工作以SiO、沥青和聚四氟乙烯为原料,通过机械融合和加热包覆,制备出了氟元素掺杂的硅碳复合材料.采用SEM、TEM、XRD、红外碳硫分析、激光粒度分析、粉末电阻率和比表面积测试仪等对样品进行了微观形貌表征和物相结构分析。电化学测试表明:当聚四氟乙烯用量为20%(质量百分数)时,SiO@C-F材料具有优异的电化学性能,可逆比容量为1426.8 mA-h/g,首次效率为77.01%,20圈容量保持率83.95%.

The F-doped SiO@C composites material were synthesized via mechanical fusion and heating coating of SiO,pitch and polyfluortetraethylene(PTFE).The morphology structure and the phase composition of the samples were characterized by SEM,TEM,XRD,infrared carbon and sulfur analysis,laser particle analyzer,powder resistivity and specific surface area.Results showed that:when the dosage of PTFE was 20%,the SiO@C-F composites had the excellent electrochemical performance,witch exhibited the reversible capacity of 1426.8 mA*h/g,initial coulombic efficiency of 77.01%and capacity retention of 83.95%after 20 cycles.