▎ 摘　　要

NOVELTY - Catalyst is claimed. The catalyst is formed by graphene oxide coated nanoparticles having particle size of less than or equal to 100 nm. USE - The catalyst is useful for preparing benzaldehyde by catalytic oxidation of styrene (claimed). ADVANTAGE - The method: has simple process, no solvent and other auxiliary agents; and is environmentally friendly, has fewer by-products of benzaldehyde, is easy to separate and purify, and is suitable for expanded production. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) preparing catalyst comprising adding nanoparticles having particle diameter of less than 100 nm into graphene oxide solution under stirring, and then vacuum until there is no liquid; and (2) use method of catalyst in preparing benzaldehyde by catalytic oxidation of styrene comprising adding styrene, hydrogen peroxide solution and catalyst into the organic solvent, stirring and reacting at 45-75 degrees C for 6-12 hours, and then centrifuging to take the supernatant, transferring clear liquid into the separatory funnel for liquid separation to obtain organic phase and the aqueous phase separately, washing the organic phase to neutral, neutralizing aqueous phase to a pH value of 8-9 and then extracting to obtain extract, washing organic phase to neutrality and combining extract, and rotary evaporating in vacuum to obtain benzaldehyde.