At a time of energy constraints and limited CO2 emissions, energy saving and emission reduction have become new challenges for ammonia synthesis. More and more researchers are focusing on ambient temperature and pressure, hoping to develop suitable catalysts to synthesize ammonia under mild or near-mild conditions. If electrical energy, light energy, and radiation energy can be introduced into the nitrogen fixation process, on the one hand, the ammonia synthesis reaction can be free from or less affected by the thermodynamic equilibrium on the conversion; on the other hand, the thermodynamic non-spontaneous reaction can also be carried out with the assistance of other energies, which will broaden the field of research on the way to synthetic ammonia.
Throughout the history of catalytic development, the study of ammonia reaction has not been stagnant for a moment. Over the past century, ammonia catalysts have been the starting point for many fundamental theoretical studies in multiphase catalysis, and they are often used as the first touchstone whenever new theories about catalysts are proposed. Starting with Fritz Haber's discovery in 1908 that ammonia could be synthesized directly from nitrogen and hydrogen, each major breakthrough in ammonia research has also left a milestone. Along with the discovery of new catalytic methods and the growing scale of ammonia industry, the research on ammonia synthesis catalysis will usher in a new round of broader and long-term development!
A series of new methods, such as bio-enzyme catalysis, organometallic biomimetic catalysis, photocatalysis and electrocatalysis, are springing up, providing unlimited possibilities for ammonia synthesis under mild conditions.