原位合成法制备石墨烯/CdS量子点复合材料, 并考察其作为锂离子电池负极材料的电化学性能. 交流阻抗揭示电解质在石墨烯/CdS量子点复合材料表面形成稳定的SEI膜, 首次放电比容量达1264.7mAh/g, 循环20次后可逆容量为888.9mAh/g. 结果显示CdS量子点提高了石墨烯结构的稳定和层间传导性, 从而导致复合材料的电化学性能明显优于单独的石墨烯材料.
Graphene/CdS quantum dot composites were prepared via in situ synthesis and its electrochemical performances as anode material for lithium-ion batteries were investigated. Ac impendence spectra reveal that electrolytes form a fine solid electrolyte interphase film (SEI) on the surface of the graphene/CdS quantum dot composites. The initial discharge capacity of the lithium-ion battery using graphene/CdS quantum dot as anode is about to 1264.7mAh/g and reversible capacity is 888.9mAh/g after 20 cycles. The results indicate that the CdS quantum dot improve the stability of the graphene structure and the conductivity between graphene sheets, so the electrochemical performance of graphene/CdS quantum dot composites as anode materials is obviously better than that of graphene materials.
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