CuO Nanosheets Prepared by Dielectric Barrier Discharge Microplasma as Catalysts for the Oxygen Evolution Reaction

A method for constructing transition metal catalysts for the oxygen evolution reaction (OER) is proposed. Facile preparation is realized in the case of no added metal source via dielectric barrier discharge (DBD) microplasma under 10 min, and the thickness of the nanosheet is only 6.5 nm. The prepared ultrathin CuO nanosheets on copper foam (CuO UTNS/CF) display a catalytic activity of 262 mV overpotential (η) at 10 mA cm–2 for the OER in alkaline media. The as-prepared electrocatalyst guarantees appealing long-term durability (>90 h) and a high turnover frequency (TOF) of 0.488 mol O2 s–1 at 426 mV. Compared to CuO/CF prepared traditionally, the overpotential of CuO UTNS/CF can be directly reduced to 38 mV. Moreover, hydroxyl radicals (•OH) were identified as the intermediate products and a possible synthesis mechanism was preliminarily put forward. As a facile technology for the OER catalyst, we believe that DBD microplasma will provide a broad perspective for researchers.