Stable and fast Si−M−C ternary anodes enabled by interfacial engineering

Abstract

For lithium storage, the co-hybridization of silicon with metal and carbon matrices is a promising strategy to mitigate the intrinsic challenges of silicon anodes. However, current Si–M–C ternary materials often suffer from nonuniform distribution of triple components, and Si is physically combined to M/C dual matrices with weak interactions. Herein, we propose an interpenetrating hydrogel-enabled methodology for the formation of chemical-bonded and uniform-distributed Si−M−C ternary materials. As a proof-of-concept illustration, commercial Si particles have been in situ immobilized within Sn nanorod-filled graphene gel framework, and are covalently bonded with Sn/G dual matrices via interfacial Si–O–Sn and Si–O–C bondings. Thanks to the rationally designed composition and structure, the Si–Sn@G gel framework anode manifests long cycling life (983 mA h g−1 in the 100th cycle at 0.5 A g−1) and good rate capability (717 and 514 mA h g−1 at 5 and 10 A g−1, respectively).