Nicopt  Alloy Dispersed by 2d Ultrathin Nico Nanosheets For Enhanced Oxygen Reduction Reaction Activities

Abstract

A novel NiCoPt ternary-alloy dispersed by 2D ultrathin NiCo nanosheets has been designed and successfully synthesized for oxygen reduction (ORR) with high activity and long-term stability. The NiCoPt/NiCo nanostructures are prepared through the artificial active collodion membrane by one-step method, and experimental data reveals that NiCoPt ternary-alloy are uniformly dispersed on the amorphous NiCo nanosheets. The optimized NiCoPt/NiCo  nanostructures show higher activities both in the onset potential and kinetic current density toward the ORR relative to the commercial Pt reference catalysts, because the NiCoPt/NiCo catalyst could lower the coverage of OH on the Pt surface, which is considered to inhibit the ORR toward water. Meanwhile, NiCoPt/NiCo nanostructures exhibit relatively long-term stability with only ~8% loss in electrochemical surface area (ECSA) for Pt and a small degradation of 24 mV in the half-wave potential for ORR after 30,000 cycles test in 0.1 M HClO 4  solution.

Keywords: NiCoPt alloy, Ultrathin nanosheets, Heterogeneous catalysis, Oxygen reduction, Electrochemistry