2020 Virtual AIChE Annual Meeting
(513bi) Earth Abundant Transition Metal Phosphide Catalysts for Highly Efficient Oxygen Evolution Reaction in Electrochemical Devices
Authors
Here, we are presenting a study of stable transition metal phosphide (TMP) based catalyst as an earth-abundant candidate with outstanding catalytic properties at active sites for OER in protic media. Activity and stability of our catalyst was tested and compared with state-of-the-art catalysts using cyclic voltammetry and chronopotentiometry experiments in 1M KOH electrolyte. The OER onset potential for our TMP-based catalyst is 1.40 V RHE (η=170 mV), that is ~100 mV lower than IrO2 nanoparticles under identical experimental conditions. A current density of 10 mA/cm2 for this catalyst is achieved at η=270 mV that is 1.3 times lower than IrO2 nanoparticles (η=343 mV), suggesting a 30% higher energy efficiency electrocatalysis using this catalyst. Our measurements indicate a low Tafel slope of 56 mV/dec that is 1.4 times lower than IrO2 (80 mV/dec), suggesting a faster OER kinetics on active sites of the TMP-based catalyst. The cost-effective and high-performance catalyst developed in this study paves the way toward an efficient energy conversion device that can work with renewable energies such as solar/wind energy to address ever-increasing energy demands in a sustainable pathway.