▎ 摘　　要

NOVELTY - Preparation of direct methanol fuel cell anode catalyst involves preparing graphene by oxidizing and stripping graphite; modifying graphene with polyethyleneimine (PEI); reacting PEI-modified graphene with chloroplatinic acid (H2PtCl6), cupric chloride, sodium chloride (NaCl), disodium citrate dihydrate and sodium borohydride (NaBH4) in secondary water, and purifying to obtain platinum copper/graphene catalyst; and reacting PEI-modified graphene with H2PtCl6, NaCl, disodium citrate dihydrate and NaBH4 in secondary water, and purifying to obtain platinum/graphene catalyst. USE - Method for preparing anode catalyst used for direct methanol fuel cell (claimed). ADVANTAGE - The method is simple and has mild and controllable conditions. The platinum copper/graphene catalyst has excellent electrocatalytic activity for methanol oxidation. DETAILED DESCRIPTION - Preparation of direct methanol fuel cell anode catalyst involves: (A) adding graphite (1 g) and sodium nitrate (1 g) to 98% sulfuric acid solution (46 ml), mechanically stirring for 20 minutes in ice bath, slowly adding potassium permanganate (6 g) and secondary water (80 ml), controlling at 85-95 degrees C, continuously stirring for 30 minutes, adding secondary water (200 ml) and slowly adding 30% hydrogen peroxide solution (6 ml), filtering while hot, washing with secondary water until washing solution is neutral, dispersing product in secondary water (500 ml), and ultrasonically treating under 150-200 W for 2 hours to obtain uniformly dispersed monolithic graphene; (B) dispersing graphene (20 mg) in sodium chloride solution (1 mol/L, 50 ml), ultrasonically treating for 1 hour, adding PEI (1.08 g), continuously ultrasonically treating for 4.5 hours, centrifuging at 8000-10000 revolutions/minute (rpm) for 3-5 minutes, rinsing with secondary water, and vacuum drying at 40 degrees C for 48 hours to obtain PEI-modified graphene; (C) ultrasonically dispersing PEI-modified graphene (20 mg) in secondary water (30 ml), sequentially adding H2PtCl6 (40 mg), cupric chloride (16 mg), NaCl (22 mg) and disodium citrate dihydrate (210 mg), continuously ultrasonically treating for 30 minutes, consequently slowly adding NaBH4 solution (0.15 M, 30 ml) under magnetic stirring, magnetically stirring at 200-350 rpm for 24 hours, centrifuging at 8000-10000 rpm for 3-5 minutes, rinsing with mixture of secondary water and ethanol (1:1 volume ratio), and vacuum drying at 40 degrees C for 48 hours to obtain platinum copper/graphene catalyst comprising platinum copper nanoparticles with particle size of 4-6 nm (55-65 wt.%); and (D) ultrasonically dispersing PEI-modified graphene (20 mg) in secondary water (30 ml), sequentially adding H2PtCl6 (40 mg), NaCl (22 mg) and disodium citrate dihydrate (210 mg), continuously ultrasonically treating for 30 minutes, consequently slowly adding NaBH4 solution (0.15 M, 30 ml) under magnetic stirring, magnetically stirring at 200-350 rpm for 24 hours, centrifuging at 8000-10000 rpm for 3-5 minutes, rinsing with mixture of secondary water and ethanol (1:1 volume ratio), and vacuum drying at 40 degrees C for 48 hours to obtain platinum/graphene catalyst comprising platinum nanoparticles with particle size of 3-5 nm (55-65 wt.%).