First, a layer of dopamine was coated on the surface of carbon-coated silicon (Si NPs) nanoparticles to form polydopamine through polymerization, which was then filtered together with the GO mixture and thermally reduced to form a Si@C-rGO composite. The composite formed strong covalent bonds and hydrogen bonds between graphene and carbon-coated silicon, as shown in Figure 2, avoiding the agglomeration of silicon and the stacking of graphene.