▎ 摘　　要

NOVELTY - Preparing blue titania composite wrapped with graphene on which platinum nanoparticles are photo-deposited involves preparing blue titania nanoparticles, preparing blue titania nanoparticles wrapped with graphene by mixing the blue titania nanoparticles with a graphene oxide solution and then subjecting to vacuum heat treatment, preparing a suspension by mixing a solution containing blue titania nanoparticles wrapped with graphene and a platinum (Pt) precursor, performing a photodeposition process of the suspension, filtering, washing, and drying to obtain crystals of blue titania composite wrapped with graphene on which platinum nanoparticles are photo-deposited. USE - Method for preparing blue titania composite wrapped with graphene on which platinum nanoparticles are photo-deposited used as photocatalyst in a selective photo-conversion process from carbon dioxide (CO2) to methane (CH4) and ethane (C2H6) and for removing CO2 (all claimed). ADVANTAGE - The method has excellent conversion rate and high industrial use, excellent stability and high reusability, C2H6 is obtained in high yield, and controls composition in the complex, and adjusts the time of optical conversion. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a method for selectively converting CO2 and water vapor into CH4 and C2H6, which involves reacting CO2 and water vapor in a gas phase using photo-deposited graphene-wrapped blue titania complex as a photocatalyst, where gas phase reaction is a selective photo-conversion method of CO2; and (2) a method for removing CO2, which involves using the selective light conversion method.