▎ 摘　　要

NOVELTY - A copper compound-graphene oxide composite does not exhibit absorption derived from hydroxyl group or carbonyl group, and exhibits absorption derived from carbon-oxygen groups, measured based on infrared absorption spectrum. USE - Copper compound-graphene oxide composite used as photocatalyst in apparatus for producing hydrogen (all claimed). ADVANTAGE - The copper compound-graphene oxide composite has excellent photocatalytic activity and stability, and stably enables manufacture of hydrogen by decomposition of water. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) manufacture of copper compound-graphene oxide composite, which involves mixing a copper compound and graphene oxide in an inert solvent to prepare a suspension, and irradiating light having wavelength of 100-800 nm; (2) manufacture of hydrogen, which involves irradiating light to a hydrogen source containing water and/or alcohol in the presence of the copper compound-graphene oxide composite; and (3) hydrogen production apparatus, which consists of the copper compound-graphene oxide composite as a catalyst.