Graft copolymer coated silicon-based material and preparation method thereof

According to a graft copolymer coated silicon-based material and a preparation method thereof provided by the invention, a polyacrylic acid grafted benzimidazole copolymer coats the surface of the silicon-based material, and the polyacrylic acid and the benzimidazole copolymer have strong covalent bonds so as to ensure the compatibility of the two substances; the copolymer has certain strength so that the volume expansion of the silicon material can be effectively inhibited; a hydrogen bond formed by PAA in the copolymer and a silicon substrate, especially SiO, has good coating stability, and PAA-g-PBI has a three-dimensional network structure and an effect of reversible ionic bond reconstruction, and a specific structure can show a high adhesive force, high mechanical strength and self-healing characteristics to silicon, and can effectively adapt to volume expansion and shrinkage of a silicon-based material; and the structural stability can still be maintained after a huge volume change is generated so that