▎ 摘　　要

Carbon nanoparticles/graphene composites have been prepared from a popular and readily available biomasses sodium alginate as raw materials. Commercial quartz sand was used as reusable substrate in this experiment. The amount of quartz sand plays important role in the structure of carbon nanoparticles/graphene composites. Our results show that the thin graphene sheet and small carbon nanoparticles could shorten the diffusion length for lithium ions and ensure high reversible capacity for the carbon material. In addition, the mesopores in the materials could provide a highly accessed system that facilitates electrolyte transport and lithium ion diffusion in the electrode materials.