Graphene solar cell and preparation method thereof

The invention relates to a graphene solar cell. A photo-anode of the graphene solar cell comprises a first electrode layer (302), a nanometer crystal coating and a dye layer (301) on the surface of the nanometer crystal coating. The graphene solar cell is characterized in that the nanometer crystal coating is a composite thin film composed of a semiconductor nanometer wire core (101) wrapped by a graphene layer (102), the nanometer wire core (101) is horizontally arranged on the surface of the first electrode layer (302) where a texture (002) is preset, and a deposit mask (500) is deposited on the outer layer of the nanometer wire core (101) to form the graphene layer (102). Graphene in the graphene solar cell is arranged on the electrode layer in the direction parallel to the sunlight incidence direction, and therefore the absorption of the graphene layer on sunlight is reduced, the number and the conduction efficiency of activated electrons in dye sensitizer are increased, and the light efficiency of the so