The influence of surface finishing on the electrocatalityc properties of nickel for the oxygen evolution reaction (OER) in alkaline solution

Abstract-The oxygen evolution reaction (OER) was investigated at 60‘C in 15wt% NaOH solution on nickel electrodes. Different surface treatments such as sandblasting and/or chemical pickling were employed. Fresh and aged electrodes were subjected to electrochemical measurements. The galvanostatic electrochemical ageing was performed for 21 days, applying an anodic current equal to 150mAcm-“. From the Tafel plots for the OER, two well-defined Tafel slopes were observed for all the electrodes, before and after the electrochemical ageing. This behaviour is due to the transformation of Ni(OH), to p-NiOOH, which is the “right type of oxide” for the oxygen evolution reaction. The kinetic parameters obtained on the electrodes with different surface finishing show that the sandblasted/pickled nickel substrate loses its electrocatalytic properties for the OER early on in the experiment. 80 1997 International Association for Hydrogen Energy