硅纳米粒子聚苯胺包覆改性及其嵌/脱锂电化学性能  

Lithiation/De-lithiation Electrochemical Properties of Polyaniline-Coated Silicon Nanoparticles

作　　者：杨昱霖 高铭 梁静爽 董星龙[1] 曹国忠[1,2] 

机构地区：[1]三束材料改性教育部重点实验室,大连理工大学材料科学与工程学院,大连116024 [2]华盛顿大学材料科学与工程学院,华盛顿州98195

出　　处：《无机化学学报》2017年第12期2262-2270,共9页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金项目(No.51331006)资助项目

摘　　要：利用直流电弧等离子体蒸发法合成硅纳米粒子(SiNPs),粒径为20~30 nm。采用对氨基苯甲酸(ABA)处理SiNPs,并在ABA-SiNPs表面进行苯胺(ANi)原位化学氧化聚合,形成核/壳型聚苯胺包覆硅纳米复合粒子(PANi-SiNPs)。FTIR、DSC、XRD、TEM等分析结果表明,ABA与SiNPs之间形成了化学键,粒子表面引入了ANi基团,复合粒子中PANi质量含量约为62%。电化学性能测试表明,PANi包覆层的存在大幅度提高了SiNPs的循环稳定性能,在100 mA·g^(-1)的电流密度下循环100次后,电池容量保持率为92.5%,远高于未改性的SiNPs的性能。聚苯胺包覆改性SiNPs,改善其导电性能的同时,可以极大地缓冲充/放电过程中的体积变化,提高电极的循环稳定性能。Silicon nanoparticles （Si NPs） have been prepared by DC arc-discharge plasma, which were pretreated by 4-aminobenzoic acid （ABA） and further in situ coated by the conductive polyaniline （PANi） on its surface, thus the core/shell type polyaniline-silicon nanoparticles （PANi-Si NPs） composite was fabricated. Analysis results by means of Fourier transform infrared spectroscopy （FTIR）, differential scanning calorimetry （DSC）, transmission electron microscopy （TEM） and X-ray diffraction （XRD） indicate that ABA and Si NPs are connected by chemical bonds, and the aniline （ANi） group has been grafted onto the surface of Si NPs. The content of PANi in the composite particles is about 62%. As an anode material for Li-ion batteries, the existence of PANi coating layer can greatly improve the cycle stability of Si NPs-containing electrode. About 92.5% of the initial capacity can be maintained after 100 cycles at current density of 100 mA·g-1. The incorporation of PANi can make the active Si NPs surrounded by the conformal conductive coating, not only providing good electrical connection to Si NPs, but also accommodating huge volume change of silicon during the charge-discharge process to greatly enhance its cycling performance.

关 键 词：锂离子电池 对氨基苯甲酸 聚苯胺-硅纳米复合材料 聚合改性 循环稳定性能 

分 类 号：O646[理学—物理化学]