Photonic Sintering as an Electrode Structuring Process to Improve Electrocatalytic Activity and Durability in Anion Exchange Membrane Water Electrolysis

Abstract

Hydrogen production via water electrolysis is essential for achieving carbon-free energy. However, enhancing the performance of these systems, particularly at the electrode level, remains challenging. Photonic sintering (PS) is proposed as a highly effective post-treatment method for electrodes, highlighting the importance of electrode design and optimization. PS significantly enhances the catalytic activity and durability of spinel-type copper-cobalt oxide-based anodes for the oxygen evolution reaction and Pt@C-based cathodes for the hydrogen evolution reaction, which are attributed to structural and chemical modifications, including active site control, optimized surface chemical bonding, improved catalyst-substrate adhesion, and generation of a reduced surface. PS-treated electrodes maintain well-preserved electrochemical active sites and pore structures, which are crucial for activation polarization and mass transport kinetics. Consequently, an anion exchange membrane water electrolysis cell with PS-treated electrodes achieved 89.57% cell efficiency, 3.91 W cm-2 area-specific power at 1.8 V, and a low degradation rate of 0.049 mV h-1 (at 0.5 A cm-2) and 0.136 mV h-1 (at 1.0 A cm-2) over 500 h. This research overcomes the traditional trade-off between activity and durability, indicating that PS can be widely applied across various energy fields, including electrochemical storage and conversion.