Ionized Jet Deposition of MoS2 on Gas Diffusion Layer Electrodes for Next Generation Alkaline Electrolyzers

This study focuses on optimizing MoS2 catalysts for the hydrogen evolution reaction (HER) in anion exchange membrane (AEM) electrolyzers. A scalable Ionized Jet Deposition (IJD) technique is employed to deposit MoS2 onto various carbon supports, exploring the relationship between substrate properties and catalytic performance. The results demonstrate that substrate choice plays a pivotal role in enhancing HER activity and durability. MoS2 deposited on Freudenberg carbon support exhibited the best catalytic activity, achieving a current density of 10 mA mu g(-)(1)Mo at -0.48 V versus RHE in an alkaline environment, even with a low catalyst loading (12-49 mu g cm(-)(2)). Conversely, sulfur-doped carbon supports showed lower HER activity but superior stability, with a minimal voltage degradation of just 0.025 V after 6 h of testing at 10 mA cm(-)(2). To further understand these results, bubble evolution studies, and contact angle measurements are conducted. Stable electrodes demonstrated small contact angles and enhanced bubble release from the surface, indicating the importance of hydrophilicity in improving performance and durability. This work highlights the synergy between scalable synthesis techniques and substrate optimization, offering a promising path for advancing cost-efficient, durable electrocatalysts in large-scale AEM electrolyzers for green hydrogen production.