A High Performing Long Life Anion Exchange Membrane Water Electrolyzer with Base Metal Catalysts

Anion exchange membrane (AEM) electrolyzers are a relatively new technology for renewable hydrogen production. AEM electrolyzers have the key advantage that, they can start and stop quickly, and in principle, they do not require precious metal catalysts. Unfortunately, prior to our work, the lifetime of the electrolyzers has been limited unless preecious metals are used.

Here we report the performance of the first AEM electrolyzer to show industrially relevent lifetimes without using precious metals. The electrolyzer had a stainless-steel anode catalyst， a modified Raney nickel cathode catalyst， and a tetramethyl imidazole functionalized styrene membrane. The cell showed current densities at 60 °C of 1 A/cm² at 1.82 V and 3 A/cm² at 2.1- 2.4 V. A steady state run at 1 A/cm² showed stable performance at 1.82 V for over 12000 hours, with no sign of membrane or catalyst degradation. These results demonstrate that high current densities and long lifetimes can be obtained with AEM electrolyzers without requiring precious metal catalysts.