▎ 摘　　要

NOVELTY - Composite photocatalyst (I) comprising graphene carbon nitride as support carrier, and silver carbonate in a mass ratio of 1:99-10:90, is new. The silver carbonate is uniformly deposited on the graphene carbon nitride to form a heterojunction structure which degrades 10 mg/l concentration of methyl orange. The composite photocatalyst rapidly degrades the methyl orange for 40 minutes and the degradation rate of methyl orange reaches to 92%, after 120 minutes. USE - (I) is useful in sewage treatment and solar energy conversion. ADVANTAGE - (I) has high photocatalytic activity, wide range of visible light response, good application prospect and economic benefit. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparing the composite photocatalyst (I).