An inorganic photocatalyst with a novel 3D star topology (ST) framework was obtained via multiple cross-linking of biocoordination polymers in one-step solvothermal conditions. It possessesd a large surface area (149.36 m(2).g(-1)), among the highest value of the current reports, and represented the quantum size effect because of its 3D ST structure. The amino acid L-cysteine was introduced into the synthesis system to lead generation of the biometic coordination polymer through the amino acid dehydrate condensation and multiple cross-linking.