▎ 摘　　要

NOVELTY - Surface-modified powder comprises first polar aprotic solvent on powder surface, where the first polar aprotic solvent has dielectric constant of 5 or more and surface potential of 20 mV or more. USE - The surface-modified powder is useful for preparing silicon and/or graphene powder and in composite material (all claimed). DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) method for preparing silicon and/or graphene powder involves dispersing graphene oxide in second polar aprotic solvent, mixing the dispersed graphene oxide with the surface-modified powder, heating mixture at specific temperature under presence of mixture of hydrogen and argon gas and reducing graphite oxide to graphene; and (2) composite material comprising graphene and 10-90 wt.% surface-modified powder.