Extraordinary Hydrogen Evolution and Oxygen Evolution Reaction Activity From PPy@FeCo-LDH/NF Bifunctional Electrocatalyst in Alkaline Solution

Abstract

Alkaline water electrolysis is a promising technique for the production of hydrogen and oxygen. Nevertheless, the development of low-cost, high-activity metal-based electrocatalysts that can effectively catalyze the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) remains a significant challenge. Herein, we polymerized Polypyrrole (PPy) with FeCo layered double metal hydroxide grown in situ on nickel foam (NF) (FeCo-LDH/NF) by electrochemical polymerization to acquire composite material PPy@FeCo-LDH/NF. As a promising electrocatalyst with dual functionality for the HER and OER, the HER overpotential of PPy@FeCo-LDH/NF was 153 mV, and the OER overpotential was 245 mV at a current density of 10 mA·cm−2. It was because that PPy increased the number of active adsorption sites, which in turn regulated the ion transfer rate between the electrolyte and the prepared catalyst. At the same time, after 24 h of stability testing, the HER and OER capacitance retention rates were 96.7% and 97.1%, respectively.