Advanced Cathode Design for Anion Exchange Membrane Water Electrolysis

The shortage of fossil fuel supplies, as well as the concerning quantities of greenhouse gases in the environment, have been the primary driving forces for substantial research into alternate energy generation and storage. Renewable energy is a need in today's civilization, and hydrogen plays an important role in it due to its high caloric value and minimal carbon emissions. Anion exchange membrane water electrolyzers (AEMWE) have been extensively researched in recent years because they combine the benefits of two well-known electrolyzer technologies: alkaline water electrolyzers (AWE) with low-cost and abundant earth materials, and proton exchange membrane water electrolyzers (PEMWE) with high efficiency, compact design, and high cost due to the use of platinum metal group (PGM) catalysts. In AEMWE, oxygen evolution (OER) at the anode side is a slow reaction, as it is under PEMWE, but hydrogen evolution reaction (HER) at the cathode side also becomes sluggish in neutral and alkaline environments. Efficient and stable catalysts for hydrogen evolution reactions are required to improve the efficiency of the water-splitting process and to make hydrogen more widely available. The following research focuses on self-supported NiMo electrocatalysts synthesized by hydrothermal and electrodeposition approaches. Different supports: Ni mesh, Ni paper, Ni foam, and carbon paper were tested to establish their robustness for further scalability purposes. The catalyst synthesized by co-electrodeposition means was optimized to reach high current densities (>1A cm-2) at low overpotentials using one-step synthesis. The scalability of the electrodeposition was performed on a 5cm2 Ni mesh, but further studies are planned in the following future. The next steps and future projects are described, including other methods for high-performance HER catalyst design, strategies for improving catalyst stability, and anion exchange membrane water electrolyzer (AEMWE) real device implementation.