Platinum Supported on a Hybrid of Nickel and Tungsten Carbide on New-Diamond Electrocatalyst for Methanol Oxidation and Oxygen Reduction Reactions

A hybrid of nickel and tungsten carbide on new-diamond (Ni-WC/nD) was synthesized by a microwave-assisted method, in which nickel(tungsten) hydroxide was deposited on carbon black and then reduced carbothermally under N-2 atmosphere. Pt nanoparticles (NPs) were deposited on the hybrid to form the Pt/Ni-WC/nD electrocatalyst. XRD and TEM were used to investigate the structure and morphology of Pt/Ni-WC/nD, respectively. The results revealed that Ni and WC particles formed on carbon black during the reduction of nickel(tungsten) hydroxide at 1300 degrees C under N-2, and the amorphous carbon was translated to new-diamond as a result of the catalysis of Ni. The Pt NPs deposited on Ni-WC/nD exhibited a good affinity with the support. We demonstrated that Pt/Ni-WC/nD was an active electrocatalyst for the methanol oxidation reaction (MOR) and the oxygen reduction reaction (ORR). Pt/Ni-WC/nD exhibited a better electrocatalytic activity and durability than Pt/C electrocatalyst for the MOR and ORR. This can be attributed to the strong interaction between the Ni-WC/nD support and Pt and the excellent stability of the new-diamond.