▎ 摘　　要

NOVELTY - A palladium (Pd)/titanium dioxide/graphene (G) catalyst comprises 10-50 mass% catalytically active component Pd, 5-15 mass% titanium dioxide, and 35-85 mass% G in which titanium dioxide/G is catalyst carrier, and Pd has particle diameter of 2-4 nm which are uniformly distributed on the surface of catalyst carrier. USE - Palladium/titanium dioxide/graphene catalyst for direct methanol fuel cell. ADVANTAGE - Palladium/titanium dioxide/graphene catalyst is stable and resistant to methanol, and has excellent electro-catalytic activity for oxygen reduction. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of Pd/titanium dioxide (TiO2)/G catalyst which involves preparing graphene with concentration of 40-50 g/L of sulfuric acid suspension, placing in ice bath, adding potassium permanganate (KMnO4) in which mass ratio graphene:KMnO4 is 1:10-1:20, reacting at 30-40 degrees C for 1-3 hours while stirring, adding deionized water in which graphene concentration is diluted to 0.6-1.2 g/L, raising temperature to 90-100 degrees C and reacting for 10-20 minutes, adding 0.5-0.75 mass% hydrogen peroxide (H2O2) solution to stop the reaction in which mass ratio H2O2:graphene is 1:1000-1:800, washing with 1-1.5 mol/L hydrochloric acid (HCl) solution, centrifuging to remove supernatant with rotating speed of 3000-5000 rpm, repeating washing and centrifuging until supernatant is free of SO42-, collecting and vacuum drying at 40-60 degrees C for 10-14 hours to obtain graphene oxide, dispersing graphite oxide in low carbon alcohol solvent to prepare 0.5-1 g/L graphene oxide suspension liquid, ultrasonically dispersing for 1-2 hours, adding titanium compound based on 5-15 mass% TiO2, performing hydrolysis reaction to obtain TiO2/graphene oxide suspension, adjusting pH to 10-14 using 0.05-0.2 mol/L sodium hydroxide, adding palladium compound based on 10-50 mass% Pd, refluxing at 120-130 degrees C for 3-4 hours in the presence of nitrogen, reducing Pd loaded on TiO2/graphene oxide carrier using low carbon alcohol, reducing temperature to 80-95 degrees C, adding hydrazine hydrate in which volume-to-mass (ml:g) ratio hydrazine hydrate:graphene oxide is 9-11:10, reducing graphene oxide for 20-40 minutes, reducing temperature to room temperature, adding 0.05-0.2 mol/L HCl solution to adjust pH to 2-4, standing for 8-12 hours, centrifuging to remove supernatant with rotating speed of 7000-9000 rpm, repeatedly washing with deionized water and centrifuging until supernatant is free of Cl-, and vacuum drying at 40-60 degrees C for 10-14 hours. DESCRIPTION OF DRAWING(S) - The drawing shows an X-ray diffraction pattern of a palladium/titanium dioxide/graphene catalyst. (Drawing includes non-English language text).