Robust water splitting based on new microporous hybrid iron cobalt phosphonate as efficient bifunctional electrocatalyst

Abstract

The facile synthesis of microporous hybrid bimetallic iron-cobalt phosphonate (FeCoNAPH) has been reported under easy hydrothermal condition without using any kind of template. With the lower overpotential values of 154 and 132 mV at 10 mA cm-2 and having lower Tafel slopes, the electrocatalyst displays outstanding catalytic activities for OER and HER, repetitively in basic medium. The as-synthesized FeCoNAPH is a cost-effective material employed in practical applications, and it is analogous to the standard catalysts such as IrO2 and Pt/ C (10 wt%). Having a high specific surface area with regular microporosity, the FeCoNAPH displays exceptional electrocatalytic activity, which could be utilized for commercialization purposes in the future to substitute the high-cost effectiveness and scarcity of noble metals. Additionally, the as-synthesized electrocatalyst exhibits long-term durability with the required cell potential of 1.43 V to attain 10 mA cm-2 for a two-electrode overall water splitting (OWS) system. Notably, the spherical structure helps in the production of a greater number of electroactive sites, which leads to a faster rate of kinetics of the development of electroactive intermediate species.