RESUMO
The emerging concept of the hydrogen economy is facing challenges associated with hydrogen storage and transport. The utilization of ammonia as an energy (hydrogen) carrier for the on-site generation of hydrogen via ammonia decomposition has gained attraction among the scientific community. Ruthenium-based catalysts are highly active but their high cost and less abundance are limitations for scale-up application. Therefore, combining ruthenium with cheaper transition metals such as nickel, cobalt, iron, molybdenum, etc., to generate metal-metal (bimetallic) surfaces suitable for ammonia decomposition has been investigated in recent years. Herein, the recent trends in developing bimetallic catalyst systems, the role of metal type, support materials, promoter, synthesis techniques, and the investigations of the reaction kinetics and mechanism for ammonia decomposition have been reviewed.