TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The quantum dot grain is cadmium selenide, cadmium sulfide, cadmium telluride, indium phosphide, lead sulfide, indium nitride, tantalum nitride, gallium arsenide, gallium phosphide, zinc oxide, iron oxide, tungsten oxide, tin oxide and/or titanium dioxide. The quantum dot reaction precursor is cadmium nitrate, cadmium chloride, lead nitrate, lead chloride, potassium sulfide, sodium sulfide, hydrogen sulfide, NaSeSO3, TiCl4, NH4OH, HCl and/or phthalate tetrabutyl ester; and the quantum dot reaction precursor generates graphene-quantum dot solution in situ. The oxide film is titanium dioxide, zinc oxide, zinc sulfide, tin oxide, niobium oxide, aluminum oxide, indium oxide, copper oxide and/or silicon dioxide. The substrate material is transparent conductive glass, metal substrate, carbon material substrate, polyethylene substrate, polystyrene substrate or polyester substrate. The constructed solar battery comprises graphene-quantum dot compound film on the conductive substrate, electrolyte on the compound film and a counter electrode covered on electrolyte. The electrolyte is liquid electrolyte, quasi solid electrolyte or solid electrolyte. The electrolyte is liquid electrolyte of acetonitrile, valeronitrile, methoxypropionitrile, ethylene carbonate, propylene carbonate, gamma -butyl propyl ester, iodine simple substance, lithium iodide, pyridine iodate and/or fuse salt, quasi solid electrolyte of sorbierite derivative, copolymer of vinylidene fluoride and hexafluoropropylene, polyacrylic acid polymer, trimethoxysilane, multi-pyridine side-chain radical polyamide branched macro-molecular derivative, silica nano grains and/or carbon nano grains, or solid electrolyte of cuprous rhodanide, cuprous iodide, nickel oxide, poly(3-octyl thiophene), polypyrrole, polyoxyethylene, polyacrylonitrile, copolymer of epichlorohydrin and/or ethylene oxide and polyvinylidene fluoride. The counter electrode is metal electrode, carbon electrode and macromolecular electrode. The photoelectrical conversion efficiency of constructed solar battery is 0.3-0.8%.