Dopamine‐Assisted Coral Films of Cobalt as Bifunctional Electrodes for Overall Water Splitting

Abstract

Coral‐type cobalt nanostructures are electrodeposited on a dopamine‐modified nickel plate under ordinary conditions. The deposited electrodes are studied for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) as bifunctional electrodes for overall water splitting. These electrodes show overpotentials of 300 and 290 mV for OER and HER respectively, at a benchmark current density of 10 mA cm−2. In case of OER, the absence of dopamine gives higher overpotential and exfoliation of Co coating. In the presence of dopamine, the electrodes show lower overpotential and better long‐term stability for both HER and OER for overall water splitting. Hence, the present Ni−dopamine−Co electrode interface can be a better bifunctional electrode for the overall water splitting reaction.