▎ 摘　　要

NOVELTY - A method for chemically depositing cadmium selenide/reduced graphene oxide composite thin film on a solid substrate, comprises (a) immersing a substrate in aqueous solution of cadmium compounds for 10-25 seconds so as to form a uniform layer of cadmium ions on the surface of substrate, (b) rinsing the substrate with double distilled water for 10-30 seconds, and (c) inserting the substrate in aqueous solution of sodium selenosulfate for 10-25 seconds for the reaction of cadmium ions with selenium ions to form cadmium selenide film on the substrate surface, where the concentration of cadmium chloride in the aqueous solution is 0.05-0.25 M, and the concentration of sodium selenosulfate solution is 0.05-0.25 M. The steps (a) to (c) are repeated to produce cadmium selenide/reduced graphene oxide composite film on solid substrate of desired thickness at temperature 300-343K. USE - The method is used for chemically synthesizing cadmium selenide/reduced graphene oxide composited thin film coating on solid surfaces used in photoelectrochemical cells. ADVANTAGE - The cadmium selenide/reduced graphene oxide composite thin film is nanocrystalline, compact and photoactive.