Chromium doping: A new approach to regulate electronic structure of cobalt carbonate hydroxide for oxygen evolution improvement

Highly efficient catalysts are required to solve the intrinsically sluggish kinetics of oxygen evolution reaction (OER). Herein, chromium doped cobalt carbonate hydroxide nanowire array on Ni foam (Cr-CoCH/NF) has been synthesized for the enhancement of OER activity and stability. Compared with pure CoCH/NF, Cr 0.2 -CoCH/NF, the optimal doping of Cr, shows a low overpotential of 203 mV at the current density of 10 mA cm −2 and a small Tafel slope of 84 mV dec −1 in 1.0 M NaOH. In addition, there is little deterioration in electrocatalytic performance after 1000-cycle cyclic voltammetry and the high activity can be maintained over 25 h. Density functional theory calculations reveal the Cr doping can regulate the electronic structure of nearby Co active center to achieve great enhancement of OER activity.