Atomic Layer Deposition of NiO on Self‐Supported Co3O4 Nanoneedle Array for Electrocatalytic Methanol Oxidation Reaction

Abstract

Developing efficient transition metal oxide catalysts is still challenging for direct methanol fuel cells. Herein, an atomic layer deposition method to prepare NiO on a self‐supported Co3O4 nanoneedle array grown on a porous nickel foam substrate (NiO–Co3O4 NA@NF) as the electrode for the methanol oxidation reaction (MOR) is reported. The synergistic effect between the NiO and Co3O4 components as well as the specific 3D nanoarray structure can endow the prepared NiO–Co3O4 NA@NF with a very promising MOR catalytic activity. As a result, the NiO–Co3O4 NA@NF catalyst shows a low onset potential (1.27 V vs reversible hydrogen electrode [RHE]), a high current density (173 mA cm−2@1.524 V vs RHE), and good stability in MOR. This work demonstrates the feasibility of the atomic layer deposition strategy in fabricating complex oxides‐based high‐performance electrocatalysts.