无定形碳包覆锡基负极材料的制备及其电化学性能

Preparation and electrochemical performance of amorphous carbon coated tin-based anode materials

氧化锡因其较高的理论比容量颇受关注,在电化学研究应用中,与碳材料复合改性后可作为锂离子电池的负极材料。本文选用五水四氯化锡为锡源,氧化石墨烯和葡萄糖作为碳源,采用简单水解法、水热处理,可以大量合成SnO2/C复合材料。通过对产物进行结构的表征、微观形貌的分析及电化学性能测试,结果表明,氧化锡纳米颗粒均匀分散于无定形碳之间,复合材料循环100圈后放电比容量为541mA·h/g。相比于纯SnO2纳米颗粒,无定形碳能够抑制氧化锡的体积效应,提高材料整体的导电性,同时改善材料的循环稳定性。

Tin oxides have attracted much attention as a negative material for lithium-ion batteries due to its high theoretical specific capacity and low cost. In this work, taking tin tetrachloride pentahydrate as tin source and graphene oxide (GO)/C6H12O6 as carbon source, the composite of SnO2 dispersed into amorphous carbon has been synthesized by hydrolysis and carbonization in large scale. The composite structure and morphology of the products are characterized, and the electrochemical properties of the product are analyzed by electrochemical tests. SnO2 nanoparticles are homogeneously dispersed in the matrix of amorphous carbon. After 100 cycles, the discharge capacity of the composite is 541 mA.h.g^-1. Amorphous carbon can effectively suppress the volume change of SnO2 particles during charging/discharging, and improves the conductivity of the composites and the cyclic stability. It leads to an improved electrochemical properties.