Influence of electrooxidation of Ni wire electrodes on the kinetics of oxygen evolution reaction studied in 0.1 mol dm^-3 NaOH

This work reports on oxygen evolution reaction (OER), studied at nickel wire electrode material. Electrocatalytic behavior of non-oxidized and electrooxidized Ni wire samples was evaluated in 0.1 mol dm^-3 NaOH solution for the potential range: 1600-2000 mV vs. RHE. The performance of nickel electrodes was examined by alternating current (a.c.) impedance spectroscopy, cyclic voltammetry and Tafel polarization measurements. Electrochemical oxidation of Ni wire radically increased the kinetics of the OER, exhibited through reduced charge-transfer resistance parameter and considerably modified Tafel polarization slopes. (author)