▎ 摘　　要

NOVELTY - Nickel-gold/palladium three-layer core-shell electro catalyst comprises reduced graphene as carrier. The core comprises non-precious metal nickel non-precious metal, where gold and palladium are assembled. The average size of metal nanoparticles are 7.4 nm, with nuclear -middle layer-shell three special structure and dispersing graphene oxide homogeneously in multi-functional three-layer core-shell structure of catalyst. USE - The nickel-gold/palladium three-layer core-shell electro catalyst is useful for oxidising ethanol and reducing oxygen. ADVANTAGE - The preparation of catalyst is simple. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing nickel-gold/palladium three-layer core-shell electro catalyst comprises reduced graphene as carrier, comprising (i) preparing graphene oxide by Hummers method; (ii) dispersing oxidized graphene in deionized water to obtain aqueous solution of graphene oxide; (iii) adding nickel precursor into aqueous solution of graphene oxide and dispersing under ultrasonic condition obtain mixed solution; (iv) adding excess of reducing agent solution drop wise into mixed solution and stirring to obtain nickel elemental and reduced graphene oxide; (iv) washing black precipitate with deionized water to neutralize black precipitate, dispersing black precipitate in deionized water to obtain aqueous solution of reduced-grained graphene-supported elemental nickel; (v) dissolving gold(III) chloride trihydrate to obtain chloroauric acid solution; (vi) adding chloroauric acid solution into aqueous solution of element nickel, dispersing ultrasonically and stirring until gold is replaced by nickel; (vii) dispersing dark precipitate neutralized with deionized water and black precipitate in deionized water to obtain aqueous solution of nickel/gold- graphene oxide; (viii) dissolving palladium dichloride in hydrochloric acid solution to obtain hydrogenchloropalladate solution; (ix) adding hydrogenchloropalladate solution drop wise into aqueous solution of nickel/gold- graphene oxide; (x) adding reducing agent drop wise, palladium, dispersing ultrasonically and stirring reaction until palladium is completely reduced to obtain Nickel-gold/palladium- graphene oxide aqueous solution; (xi) filtering Nickel-gold/palladium- graphene oxide aqueous solution to neutral and freeze-drying to obtain Nickel-gold/palladium- graphene oxide with three-layer core-shell structure, electro catalyst comprises 18- 25 wt.% nickel, 9-15 wt.% gold and 9-15 wt.% palladium.