Ammonia is considered as one of the most effective hydrogen carriers, which can be liquefied by mild compression for easy transport. After discovery of the 2nd generation Haber-Bosch catalysts based on Ru-active sites by Aika et al. (J. Catal. 1972, 27, 424-431), further improvement in efficiency of ammonia synthesis is highly demanded. To realize the green ammonia production, the improvement in rate of ammonia synthesis at low temperatures is required.

  We conduct detailed microkinetic analysis to understand the true rate controlling step for conditioning reaction conditions for rate improvement. Since ammonia synthesis reaction is exothermic, the equilibrium towards ammonia is preferred at low temperatures. Novel design of reactor systems should be proposed and tested for improved rates. In addition to developing novel ammonia synthesis catalysts, the electrocatalytic synthesis of ammonia is considered to be one of the strategies for future renewable energy conversion technologies.