摘要
二硫化钼(MoS2)是典型的层状过渡金属硫化物,作为锂离子电池负极材料具有巨大的应用前景.文章采用热分解的方法合成了中空球形的纳米MoS2,然后以盐酸多巴胺为碳源,制备了表面包覆碳层的中空MoS2负极材料.采用XRD,Raman,SEM等方法系统表征了 MoS2/C复合材料的晶型结构和形貌,MoS2/C负极材料的尺寸在150～250 nm,表面碳层厚度为40～70 nm,中空球形结构的纳米MoS2可以有效地缓解充放电过程中的剧烈体积效应,表面碳层包覆可以有效改善MoS2的导电性,同时增强了材料的结构稳定性.电化学测试表明,MoS2/C负极材料初始放电比容量高达1 132.1 mA·h/g,经过50次循环后,放电比容量仍有587.4 mA·h/g,显示出了在锂离子电池负极材料领域的巨大应用潜力.
Abstract
Molybdenum disulfide(MoS2)is a classical layered transition metal sulfide,which exhibits excellent performance as cathode materials for lithium-ion batteries.In this research,hollow spherical nano-MoS2 was synthesized by thermal decomposition,and then the carbon coated MoS2 was prepared with dopamine hydrochloride as carbon source.Various characterization techniques such as XRD,SEM,and Raman spectroscopy were used to analyze the composition and structure of MoS2/C nano-composites.The size of MoS2/C nanocomposites is 150-250 nm and the thickness of carbon layer is 40-70 nm.The hollow spherical structure of nano MoS2 can effectively alleviate the intense volume change during cycling.The coating of carbon layer on the surface can effectively improve the conduc-tivity of MoS2,and enhance the structural stability.As a result,this novel ordered structure delivers a high initial specific capacity of 1 132.1 mA·h/g and remain 587.4 mA·h/g over 50 cycles,thus exhibiting great potential as an anode composite structure for durable high-rate lithium-ion batteries.
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