有色金属科学与工程2024，Vol.15Issue(2)：256-264,273,10.DOI:10.13264/j.cnki.ysjskx.2024.02.012
CO2氧化多孔Mg2Si制备微纳分级Si/C材料及储锂性能
Preparation of micro-nano hierarchical Si/C composites by CO2 oxidation of porous Mg2Si and lithium storage properties
摘要
Abstract
With the advantages of abundant reserves,stable working voltage and high energy density,silicon-based anode materials are regarded as a kind of promising anode for lithium-ion batteries.However,their high volume expansion of 300%and low ionic conductivity are very detrimental to battery cycling.In this paper,a micro-nano hierarchical three-dimensional MN-p-Si/C composite was successfully synthesized by using a one-step CO2 oxidation process with porous Mg2Si as raw material.During the oxidation process,the Mg was transformed into MgO and etched away by diluted hydrochloric acid solution,and nanoscaled voids were thus introduced in the micro porous Si system.The micro-nano hierarchical structured MN-p-Si/C not only alleviates the volume expansion of silicon during the delithiation process but also provides a three-dimensional effective channel for the transportation of ions/electrons.The carbon layer on MN-p-Si/C substantially improves the electrical conductivity of the composite.Owing to these structural advantages,the MN-p-Si/C composites demonstrated excellent electrochemical properties.Their first charge/discharge specific capacity was 2 869.2 mAh/g,2 364.5 mAh/g with an initial Coulomb efficiency of 82.41%,and the MN-p-Si/C reversible capacity could be maintained at 1 127.1 mAh/g after 200 cycles at a high current density of 1 A/g.The specific capacity retention rate was 70.9 with good application prospects.关键词
硅/碳负极/多孔结构/CO2氧化反应/Mg2SiKey words
silicon/carbon anode/porous structure/CO2 oxidation reaction/Mg2Si分类
信息技术与安全科学引用本文复制引用
郑娅,刘娟,喻强,穆艺臣,赵小玉,李小成..CO2氧化多孔Mg2Si制备微纳分级Si/C材料及储锂性能[J].有色金属科学与工程,2024,15(2):256-264,273,10.基金项目
国家自然科学基金资助项目(51862013) （51862013）
江西省自然科学基金资助项目(20202ACBL204014) （20202ACBL204014）
江西省教育厅资助项目(GJJ200854) （GJJ200854）
赣州科技创新人才计划资助项目 （）
