One step synthesis of Co-Ni bimetallic organic frameworks as a highly active and durable electrocatalyst for efficient water oxidation

Abstract

As a half-reaction in the water decomposition, the oxygen evolution reaction (OER) has limited the development and practical application of water splitting due to the kinetic speed and high overpotential. Therefore, it still exists a challenge to exploit high-performance and durable electrocatalysts for OER. Herein, a one-step hydrothermal approach was designed to prepare Co-Ni bimetallic organic frameworks (MOFs) on nickel foam (NF) substrate as a highly efficient electrocatalyst for OER under alkaline conditions. The prepared MIL-53(Co-Ni)/NF has excellent OER catalytic activity, which requires only an overpotential of 197 mV to achieve 20 mA cm−2. The proposed electrocatalyst exhibits long-term durability (>60 h) and a high turnover frequency (TOF) of 0.2806 mol O2 s−1 at 350 mV. Systematic study revealed that the coordination between Co-Ni played a significant role to improve OER performance. The present results demonstrated that bimetallic organic frameworks could be utilized to fabricate promising water-oxidation catalysts in energy conversion.