Selectivity of cobalt-based catalysts towards hydrogen peroxide formation during the reduction of oxygen

The electrochemical reduction of oxygen has been investigated for a cobalt-amine complex pyrolysed at various temperatures. The activity of the corresponding cobalt-free materials has also been studied. The selectivity of the catalysts towards hydrogen peroxide production has been determined using Koutecky–Levich analysis and rotating ring disc electrochemical measurements. A combination of the rotating ring disc data and studies of the reduction of hydrogen peroxide have been used to investigate the reaction mechanism kinetics. The selectivity towards hydrogen peroxide passes through a minimum at a pyrolysis temperature of 700 °C. The highest activity for oxygen reduction and yield for hydrogen peroxide formation was observed for the catalysts treated at higher temperatures.