Activation of powder-coated electrodes for the alkaline oxygen evolution reaction

To address the challenges of climate change, efficient green hydrogen production via alkaline water electrolysis is essential. Enhanced efficiency can be achieved not only by catalyst design, but also by pre-treatment of the catalyst-coated electrodes. In this study, we transfer previously optimized electrochemical conditioning protocols to spray-coated anodes and compare their effects with plasma treatment and ball milling. While plasma treatment enhances activity for the oxygen evolution reaction, combining plasma treatment with electrochemical conditioning further improves performance, reducing the potential required to reach 100 mA cm -2 by over 50 mV. Plasma treatment also improves catalyst-layer adhesion, reducing delamination during conditioning. However, delamination could not be fully prevented for intensive conditioning protocols involving cycling into the hydrogen evolution regime. Applying these protocols to more mechanically stable electrodes could enable further improvements. Overall, our findings highlight the importance of electrode pretreatment and optimized processing protocols to enhance both activity and stability. • Electrochemical conditioning enhances NiCoO 2 -coated anodes’ OER activity. • Optimized pre-treatments crucial for catalyst layer stability and activity. • Plasma treatment improves mechanical stability by particle sintering on support. • Combining pre-treatments can boost electrode performance by up to 50 mV at 100 mA cm -2 .