文献类型：期刊文献

中文题名：新型核壳结构硅碳复合负极材料的制备及电化学性能

英文题名：Preparation and electrochemical properties of novel silicon-carbon composite anode materials with a core-shell structure

作者：金恒超[1];孙骞[1];王际童[1];马成[1];凌立成[1];乔文明[1,2]

机构：[1]华东理工大学,化学工程联合国家重点实验室,上海200237;[2]华东理工大学,特种功能高分子材料及相关技术教育部重点实验室,上海200237

年份：2021

卷号：36

期号：2

起止页码：390

中文期刊名：新型炭材料

外文期刊名：New Carbon Materials

收录：CSTPCD;;EI(收录号：20211610233175);Scopus;WOS:【SCI-EXPANDED(收录号:WOS:000761689600010)】；北大核心:【北大核心2020】；CSCD:【CSCD2021_2022】；

基金：This work is supported by the National Science Foundation of China (U1710252, 21978097), and China Petrochemical Company Limited Fund (218025).

语种：中文

中文关键词：硅碳复合;负极材料;化学气相沉积;碳纳米纤维

外文关键词：Silicon carbon composite;Anode material;Chemical vapor deposition;Carbon nanofiber

摘要：通过对氧化硅预处理得到多组分硅pSi(Si、SiO、SiO_(2)),再利用化学气相沉积法(CVD)设计了具有核壳结构的pSi与碳纳米纤维(CNF)的复合材料(pSi-CNF)。多组分硅中Si、SiO提供电化学可逆容量,SiO_(2)可以抑制硅的体积膨胀;碳纳米纤维包覆形成的壳层结构可以有效提高复合材料的导电性,同时进一步抑制硅的体积膨胀保持核壳结构的完整。通过SEM、TEM、EDS、XRD、Raman和XPS对复合物的微观结构进行分析。结果表明:pSi-CNF的粒径为5~20μm,碳纳米纤维的直径为5~40 nm,pSi-CNF复合材料中含有Si、SiO和SiO_(2)多种组分硅,有明显特征峰;碳纳米纤维均匀包覆于硅表面,形成核壳结构。电化学性能测试表明,在0.2 A·g^(?1)的电流密度下,经100次循环后其可逆容量为1411 mAh·g^(?1),容量保持率为74%,具有良好的循环稳定性和较高的可逆容量;在1 A·g^(?1)的电流密度下,经300次循环后其可逆容量为735 mAh·g^(?1),容量保持率为86%,且具有良好的倍率性能。
Multi-component porous Si-SiOx(pSi)consisting of Si,SiO and SiO_(2)was formed by the pretreatment of SiO at 950℃for 3 h in an inert atmosphere(He)using a disproportionation reaction.Hybrids of pSi and carbon nanofibers(pSi-CNFs)with a core-shell structure were prepared by catalytic chemical vapor deposition(CVD)using Fe-Ni species as the catalyst and a mixture of CO/H_(2)/C_(2)H_(4)(volumetric ratio 3∶1∶1)as the reactant for 0.5,1 and 2 h,and were characterized by SEM,TEM,EDS,XRD,Raman spectroscopy and XPS.Results indicate that the pSi-CNF particle sizes are 5?20μm with the diameters of the CNFs being 5?40 nm.The CNFs are uniformly coated on the surface of the pSi to form a core-shell structure.Electrochemical performance testing shows that the reversible capacity of the pSi-CNF(0.5 h)remains at 1411 mAh.g^(?1)and the capacity retention is 74%after 100 cycles at a current density of 0.2 A.g^(?1).The reversible capacity remains at 735 mAh.g^(?1)at a current density of 1 A g^(?1)after 300 cycles with a capacity retention of 86%.In the pSi,Si and SiO provide the electrochemical reversible capacity.The core-shell structure with the CNF coating effectively improves the conductivity of the composites,and also inhibits the volume expansion of silicon to maintain the integrity of the core shell structure.