文献类型：期刊文献

英文题名：Valence-gradient engineering in SiO/C anode for hierarchical buffering and stable electrochemical performance

作者：Wei, Bing[1,2];Yue, Chengyan[1,2];Zhang, Binbin[1,2];Zhang, Jiacheng[1,2];Chen, Jiajia[1,2];Wu, Haodong[1,2];Wang, Xingjun[1,2];Yu, Guangsuo[1,2];Chen, Xueli[1,2];Wang, Fuchen[1,2];Fan, Maohong[3]

机构：[1]East China Univ Sci & Technol, State Key Lab Coal Liquificat Gasificat & Utilizat, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Inst Clean Coal Technol, Shanghai Engn Res Ctr Coal Gasificat, POB 272, Shanghai 200237, Peoples R China;[3]Univ Wyoming, Dept Chem & Biomed Engn, Laramie, WY 82071 USA

年份：2026

卷号：256

外文期刊名：CARBON

收录：;EI(收录号：20261820603238);WOS:【SCI-EXPANDED(收录号:WOS:001759519900001)】；

基金：This work is jointly supported by the National Natural Science Foundation of China (U21A20319) . The experiment was assisted by Analytical and Testing Center in East China University of Science and Technology.

语种：英文

外文关键词：SiO anode; Initial coulombic efficiency; Cycling performance; Hierarchical structure

摘要：Silicon monoxide (SiO) is a promising anode material owing to its smaller expansion volume and a better capacity retention during charge/discharge process than Si. However, limited to its disproportionated structure and low intrinsic electronic conductivities, SiO anode also suffers from poor initial coulombic efficiency (ICE) and reversible capacity. Here, a new insight for design SiO anode to induce valence difference in the radial direction for creating a hierarchical buffer layer structure is proposed. The controlled bulk SiO matrix maintains an amorphous phase while keeps less low valence silicon (Si0, Si1+) in the outer layer, which is suggested to result in preferential formation of Li-Si-O and Li2O phases in the outer regions during lithiation. Remarkably, the modified SiO anode achieved comparable cycling and rate performance to carbon-coating (SiO/C) composite. Furthermore, this valence-gradient design is inferred to construct an optimal hierarchical architecture consisting of a conductive carbon coating, a functional Li2O/Li-Si-O buffer layer, and a high-capacity LixSi core, which likely synergistically contributes to a LiF-rich solid electrolyte interphase (SEI) in the E-SiO(2h)/C(2h) electrode and a higher Li+ diffusion coefficient compared to SiO, as well as 500 cycles of long-term stability, a 27% reduction in volumetric expansion relative to SiO, and a 21% improvement in capacity retention at 1.0 A g- 1 compared to the SiO/C hybrid. These findings suggest novel design principles for high-performance SiO anodes.