Defective Ni3S2 nanowires as highly active electrocatalysts for ethanol oxidative upgrading

Electrochemical upgrading of biomass ethanol to value-added chemicals is promising for sustainable society. Here, we synthesize defective Ni3S2 nanowires (NWs), which show high activity towards electrochemical oxidation of ethanol to acetate. The Ni3S2 NWs are formed by the oriented attachment mechanism, and rich defects are introduced during the growth. A low onset potential of 1.31 V and high mass activity of 8,716 mAmgNi−1 at 1.5 V are achieved using the synthesized Ni3S2 NWs toward the ethanol electro-oxidation, which are better than the Ni(OH)2 NWs and the Ni3S2 nanoparticles (NPs). And the selectivity for the acetate generation is ca. 99%. The high activity of Ni3S2 NWs is attributed to the easier oxidation of Ni(II) to the catalytically active Ni(III) species with the promotion from S component and rich defects. These results demonstrate that the defective NWs can be synthesized by the oriented attachment method and the defective Ni3S2 NWs structure as the efficient non-noble metal electrocatalysts for oxidative upgrading of ethanol.