Oxygen-tailoring in SiO X /C with a covalent interface for high-performance lithium storage

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2022-01, Vol.10 (4), p.1928-1939
• Main Authors: Ge, Jiawei, Shen, Honglie, Zhou, Fei, Li, Yufang, Yuan, Ningyi, Yang, Wangyang, Zhou, Haobing, Xu, Binbin, Guo, Renping, Xu, Peng
• Format: Article
• Language: English
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/D1TA07965D

Oxygen-tailoring in silicon suboxide (SiO X ) can relieve its volume variation for highly structural integrity and form a stable solid electrolyte interface (SEI) layer. Herein, we propose the preparation of hierarchical SiO X /C with different oxygen contents and interfacially covalent Si–O–C bonds for advanced lithium ion batteries (LIBs). Oxygen-manipulating projects are performed to adjust the oxygen content in SiO X for low volume expansion (mechanical stress), in agreement with our experiment, stress distribution simulations and density functional theory analysis. The covalent Si–O–C bonds in metastable SiO X /C are constructed to enhance the adsorption of ethylene carbonate for a stable SEI layer and re-assemble the electrical field for fast interfacial charge responses. These synthetic advantages in hierarchical SiO X /C are beneficial for the structural integrity and the construction of a stable SEI layer. Prepared SiO X /C exhibits excellent electrochemical performance in terms of cyclic stability (1010.4 mA h g −1 after 300 cycles at 1 A g −1 ), highly stable coulombic efficiency and rate capability (413.6 mA h g −1 at 4 A g −1 ). The work based on oxygen-manipulating projects and interfacial covalent bonds provides deep insights into the preparation of durable SiO X -based anodes with a long lifespan and stable coulombic efficiency.