Surface-modification-assisted synthesis of in-situ graphene-doped carbon substrate coated silicon nanoparticles for boosting lithium storage performance

Improving the electrical conductivity and structural integrity of Si/C anodes is of great concern for lithium-ion batteries which can be effectively achieved by doping graphene. However, it is difficult to achieve graphene-doped Si/C composites with good interface contact and conductive architecture. Herein, an in-situ graphene-doped carbon coated silicon nanoparticles (SiNPs) with multilayer architecture is designed. SiNPs is firstly modified and coated by polymethyl methacrylate (PMMA) shell. Multilayer carbon architecture is constructed via co-pyrolysis method using PMMA and citric acid as carbon sources. It displays an excellent lithium storage performance with a reversible discharge capacity of 2117.5 mAhg−1 at 200 mAg−1. These impressive anodic properties are chiefly benefited from the ingenious carbon architecture coated SiNPs involving in-situ graphene with a strong interfacial bonding interaction. Overall, this investigation can not only broaden the application potential in LIBs for advanced Si/C anodes but also provide an alternative route on designing a graphene-related material.