▎ 摘　　要

NOVELTY - A carbon dioxide photoelectrochemical reduction device consists of a photoanode containing calcium-iron oxide/titanium dioxide complex, a cathode containing reduced graphene oxide/copper composite, a separation membrane provided between the photoanode and the cathode, and electrolyte provided on sides of the separation membrane. The device enables selective reduction of carbon dioxide to formaldehyde by irradiating light with respect to photoanode while supplying carbon dioxide into electrolyte. USE - Carbon dioxide photoelectrochemical reduction device (claimed). ADVANTAGE - The photoelectrochemical reduction device enables efficient reduction of carbon dioxide.