▎ 摘　　要

NOVELTY - Core-shell structure, which is obtained from 3D honeycomb-shaped nitrogen-doped graphitic carbon frame carbon material and a copper-containing compound through a polymer heat treatment reaction. USE - The core-shell structure is useful for reducing carbon dioxide photo-catalyst and preparing photo-catalytic carbon dioxide reduction film (claimed). ADVANTAGE - The method has simple operation, low cost and is convenient for popularization; utilizes the composite material for photo catalytic carbon dioxide reduction under visible light irradiation and enables maximum yields of 38.89 mumol/g methane and 27.78 mumol/g carbon monoxide. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing core-shell structure comprising (a) dissolving the carbon material containing copper compound and 3D honeycomb nitrogen-doped graphite carbon frame in deionized water, performing magnetic stirring, maintaining the mixture at 80-100degrees Celsius, stirring, drying, forming light blue powder to obtain copper and copper(I) oxide nano-particles embedded in a 3D honeycomb-shaped nitrogen-doped graphitic carbon frame composite material and (b) calcining the dried sample in a tubular furnace under the protection of inert gas in the step (a), heating to 500-700degrees Celsius for 0.5-2 hours at a rate of 1-10degrees Celsius /minute to obtain copper and copper(I) oxide embedded 3D honeycomb nitrogen-doped graphitic carbon frame composite material.