Ternary layered double hydroxide oxygen evolution reaction electrocatalyst for anion exchange membrane alkaline seawater electrolysis

Anion exchange membrane (AEM) water electrolyzers are promising energy devices for the production of clean hydrogen from seawater. However, the lack of active and robust electrocatalysts for the oxygen evolution reaction (OER) severely impedes the development of this technology. In this study, a ternary layered double hydroxide (LDH) OER electrocatalyst (NiFeCo-LDH) is developed for high-performance AEM alkaline seawater electrolyzers. The AEM alkaline seawater electrolyzer catalyzed by the NiFeCo-LDH shows high seawater electrolysis performance (0.84 A/cm2 at 1.7 Vcell) and high hydrogen production efficiency (77.6% at 0.5 A/cm2), thus outperforming an electrolyzer catalyzed by a benchmark IrO2 electrocatalyst. The NiFeCo-LDH electrocatalyst greatly improves the kinetics of the AEM alkaline seawater electrolyzer, consequently reducing its activation loss and leading to high performance. Based on the results, this NiFeCo-LDH-catalyzed AEM alkaline seawater electrolyzer can likely surpass the energy conversion targets of the US Department of Energy.