▎ 摘　　要

NOVELTY - Composite catalyst comprises 85-98 wt.% indium oxide (In2O3), and 2-15 wt.% graphene oxide (GO) based on 100 wt.% of total weight. USE - Composite catalyst used for carbon dioxide thermochemical catalytic hydrogenation to prepare methanol (claimed). ADVANTAGE - The composite catalyst has a more significant inhibitory effect on side reactions at low temperature, the addition of GO reduces the size of the catalyst, and also converts portion of the cubic phase In2O3 into the hexagonal phase, increases the relative concentration of surface oxygen vacancies to obtain high CO2 conversion rate of 29.4%, and a methanol selectivity of up to 98.3% in the hydrogenation reaction. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for following: (1) a method for preparing the composite catalyst, which involves preparing GO into a solution, mixing the solution with deionized water, and carrying out ultrasonic treatment, where preferable treatment time is 0.5-3 hours. The deionized water is added into metal indium salt for dissolving to obtain a metal indium salt aqueous solution. The metal indium salt aqueous solution is mixed with the GO solution obtained after ultrasonic treatment, and carried out ultrasonic treatment for 5-60 minutes, then stirred and mixed the obtained mixture and urea to form a precipitate, where metallic indium salt is preferably indium nitrate and/or indium chloride. The obtained precipitate is filtered, washed with deionized water for multiple times, preferably 3-5 times, preferably washed with deionized water, ethanol, propanol or mixture for the last time until pH of the system is 7, and filtered to obtain solid. The vacuum drying is carried out on the obtained solid to obtain a powder sample, and then roasted the powder sample. (2) an application of composite catalyst for carbon dioxide (CO2) thermochemical catalytic hydrogenation to prepare methanol, which involves loading In2O3-GO composite catalyst on the fixed bed reactor, and pre-processing the composite catalyst on the reactor in an inert gas atmosphere. The system is cooled at 150-200degrees Celsius, and then introduced reaction raw material gas and the temperature is raised to carry out the catalytic reaction.