Exploring mild condictions for ammonia synthesis has long been a major challenge. Recently, Prof. Qing Jiang in Jilin University, in collabration with Prof. Jong-Beom Baek in Ulsan National Institute of Science and Technology, and Prof. Samira Siahrostami in University of Calgary, developed a facile strategy to realize the synthesis of ammonia process based on the cheap Fe powder catalysts, achieving ammonia production of 82.5 vol% under the conditions of 1 bar and at temperatures as low as 45°C, which is much better than the state-of-the-art Haber-Bosch process (450 ℃, 25% ammonia production at 200 bar) and electrochemical methods (10-2900 ppm, ie 0.6-170 μM in electrolyte). More importantly, they pointed out that the weakly coupled Fe-N bonds formed during the reaction is the key factor to obtain this excellent performance according to the soft X-ray absorption spectroscopy of the XMCD beamline station in Hefei Light Source (NSRL). This work will be of great significance for guiding the preparation of high-efficiency ammonia synthesis catalysts in the future. 

^{[Nat.Nanotechnol. DOI: 10.1038/s41565-020-00809-9]}

Figure 4. Schematic diagram of ammonia synthesis process and N K-edge soft x-ray absorption spectrum