Abstract
Nano-structured silicon(Si)has demonstrated high capacity for lithium storage;however,it suffers from unsatisfactory cycling stability caused by large volume change and poor interface stability.Thus,it is very important to construct functional coatings on nano-structured Si to buffer the volume change and im-prove the interface stability.Herein,we successfully construct V2O3 and carbon(C)dual-layer coatings on Si nanoparticles with ultrathin and uniform thickness using a facile spray drying and chemical vapour deposition method.The as-prepared Si@V2O3@C manifests a high specific capacity of 2230 mAh g-1 af-ter 100 cycles under the current density of 200 mA g-1,showing its promising application prospect in lithium storage.In situ electrochemical impedance spectroscopy(EIS)results at different lithiation states and different cycles show a more stable interface resistance of Si@V2O3@C than pristine Si.The V2O3 and C dual coating layers not only ensure the Si nanoparticles with high structural stability by buffering vol-ume expansion and preventing electrolyte penetration,but also guarantee a superior electron transport rate because of the metallic V2O3 as well as the highly conductive carbon layers.
基金项目
National Key Research and Development Program of China(2022YFB3803501)
Key Research and Development Program of Hubei Province(2021BAA176)
Hainan Provincial Natural Science Foundation of China(522CXTD516)
Sanya Science and Education Innovation Park of Wuhan University of Technology(2022KFO027)
NETL
NSTL
万方数据