Ammonia electro-catalysis for hydrogen production: Mechanisms, materials, and scalability

The global transition towards sustainable energy solutions has intensified interest in hydrogen production with minimal emissions, positioning ammonia as a promising hydrogen carrier due to its high energy density and clean by-products. This review explores the potential of ammonia electrolysis and electrocatalyst development as viable hydrogen production methods. The necessity of this study lies in addressing the challenges of current hydrogen production techniques, including high costs and limited efficiency. Through an extensive literature survey, we identified key advancements and emerging patterns in electrocatalyst research, focusing on the roles of various catalysts such as Pt, Ru, Ni, and novel mixed oxides. Notably, the synthesis and deployment of catalysts with increased active sites and reduced charge transfer resistance have shown promising improvements in process efficiency. Our findings underscore the critical need for developing cost-effective, non-noble metal catalysts, which offer enhanced stability and reduced over potentials. This review also highlights the application of Density Functional Theory (DFT) as a predictive tool for optimizing catalyst properties and exploring reaction mechanisms. Furthermore, we discuss future directions for enhancing catalytic performance and scalability, particularly through bimetallic systems and heterostructures, which have emerged as promising avenues for further research. By proposing standardized methodologies for catalyst evaluation, this work aims to streamline future innovations in ammonia electrolysis, ultimately contributing to a sustainable hydrogen economy.