Scalable in situ condensation fabrication of amorphous SiOX@C microbeads derived from organic silane coupling agents for lithium-ion storage

Abstract

In the past few years, silane coupling agents are often used to modify the surface of silicon materials; however, researches in preparation of SiOX-based materials pyrolyzed from silane coupling agents are seldom reported. Hence, in order to prepare amorphous SiOX@C anodes for Li-ion storage, we adopted three kinds of silane coupling agents as organic silicon sources. The results show that silane coupling agents with vinyl group is the optimum organic silicon source. Owing to the strong chemical bonds of Si–O–C, amorphous SiOX particles are uniformly embedded in carbon matrix, forming monodisperse microbeads architecture with good buffer abilities. Therefore, the V-SiOX@C anodes derived from silane coupling agents with vinyl groups show good electrochemical performance, retaining a reversible discharge capacity of 940 mAh g−1 at a current density of 100 mA g−1 after 200 cycles, and it still depicts a good long-term cycling durability, maintaining 739 mAh g−1 at a current density of 400 mA g−1 after 400 cycles.