摘要
本文以三乙氧基硅烷为原料,在氧化石墨烯悬浮液中采用原位溶胶-凝胶反应和随后的H2/Ar气氛下热还原反应制备了石墨烯/Si/SiO_(x)(G//Si/SiO_(x))纳米复合材料。G//Si/SiO_(x)纳米复合材料中,粒径约20 nm的Si纳米粒子分布到非晶SiO_(x)基体中组成粒径为100~200 nm的Si/SiO_(x)纳米球随机分布在二维石墨烯片表面和层间。G//Si/SiO_(x)电极独特的纳米结构能够提供快速的电子传递通道和有效缓解循环过程中Si纳米粒子体积变化,促使电极具有良好的电化学储锂性能。作为锂离子电池负极材料,G//Si/SiO_(x)电极在电流密度200 mA/g下呈现出722.45 mAh/g的高初始可逆容量,300个循环后,可逆容量高达853.76 mAh/g,以及优异的倍率性能。
In this work,the graphene/Si/SiO_(x)nanocomposites(G//Si/SiO_(x))nanocomposites were synthesized.The synthesis process was done via a facile in situ sol-gel reaction of triethoxysilanein and graphene oxide suspension and a subsequent thermal reduction reaction under H_(2)/Ar atmospheres.The Si/SiO_(x)nanospheres with a 100-200 nm size were randomly distributed between two-dimensional graphene sheets in G/Si/SiO_(x)nanocomposites,in which crystalline Si nanodots with an approximate size of 20 nm were integrated into the amorphous SiO_(x)matrix.The unique G/Si/SiO_(x)nanostructure could provide a synergistic effect for electron transport within the electrode,accommodating the Si nanocrystals'volume variation during cycling and leading to excellent electrochemical performance.Benefiting from the unique structural features,the resulting G/Si/SiO_(x)electrode delivered exceptional rate performance and a high reversible specific capacity of 722.45 mAh/g at a current density of 200 mA/g,which remained at 853.76 mAh/g after 300 cycles.
作者
李悦
王博
吴楠
LI Yue;WANG Bo;WU Nan(Department of New Materials and Chemical Engineering,Tangshan University,Tangshan 063000,Hebei,China;State Key Laboratory of Metastable Materials Science and Technology,Yanshan University,Qinhuangdao 066004,Hebei,China;Tangshan Key Laboratory of Water Ecological Restoration Technology,Tangshan 063000,Hebei,China)
出处
《储能科学与技术》
CAS
CSCD
北大核心
2023年第9期2752-2759,共8页
Energy Storage Science and Technology
基金
唐山市科技计划项目(22130208H)
亚稳材料制备技术与科学国家重点实验室国家重点实验室开放课题(202103)。
