▎ 摘　　要

NOVELTY - Carbon sandwich copper nano-sheet electro-catalyst with sandwich structure comprises middle layer copper nano sheet with average thickness of 3-4 nm, and graphene-like layers on two sides of copper nano sheet with average thickness of 0.8-4.3 nm. USE - The carbon interlayer copper nanosheet electrocatalyst with sandwich structure is used for electrochemical reduction of carbon dioxide into methane. ADVANTAGE - The carbon-interlayer copper nanosheet electrocatalyst can prevent oxidation of copper nanosheet with high reaction activity in the atmosphere, and exhibits excellent catalytic performance in the process of selective electrochemical reduction of carbon dioxide as methane.