Facile Electrode Manufacturing Strategy for Ultra-Low Cobalt Consumption in Oxygen Evolution Reaction

Water splitting is a sustainable method of hydrogen production that is crucial for achieving carbon neutrality. However, the high cost of green hydrogen remains a major challenge. One strategy to reduce costs is the use of non-precious metal catalysts, such as Co, which is known for its excellent catalytic properties. However, the limited supply and increasing cost of Co pose challenges. In this study, we developed a method to significantly reduce Co usage in catalyst-coated substrates for anion exchange membrane water electrolysis. By incorporating a Co solution into the slurry during a printing transfer method with NiFe oxide, we achieved a 72-fold reduction in Co consumption while improving the overpotential by 12.9% (380 mV at 100 mA cm-2). In single-cell anion exchange membrane water electrolysis tests, the catalyst-coated substrate electrode delivered a current density of 900 mA cm-2 at 1.8 Vcell, outperforming NiFe oxide electrodes (630 mA cm-2). This strategy demonstrates a broadly applicable approach for reducing the use of expensive elements in green hydrogen production.