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Recently, the research team of Zeng Jie, a professor at the University of Science and Technology of China, and Si Rui, a professor at the Shanghai Institute of Applied Physics, Chinese Academy of Sciences, collaborated to achieve efficient nitrogen electroreduction to synthesize ammonia by constructing an atomically dispersed ruthenium catalyst. The ammonia production rate of this ruthenium single-atom catalyst in the electrocatalytic nitrogen reduction reaction is the highest reported so far. The result was titled Achieving a Record-High?Yield?Rate of 120.9 μgNH3mg-1?cat.h-1for N and was published in the journal Advanced Materials (?Adv. Mater.?2018, 30, 1803498) and was selected as the frontispiece. The co-first authors of the paper are Geng Zhigang, a special associate researcher at the University of Science and Technology of China, and Liu Yan, a doctoral candidate. Currently, industrial synthesis of ammonia via the Haber process requires high temperature and high pressure (150-350 atm, 350-550 C). Such harsh conditions consume 1-2% of the world's energy supply each year. In addition, the traditional Haber process for ammonia synthesis requires hydrogen as one of the raw materials, and the traditional hydrogen production process emits a large amount of CO2. Therefore, it is particularly important to explore catalytic reactions for ammonia synthesis under mild conditions. The electrochemical reduction of nitrogen to synthesize ammonia can be carried out at normal temperature and pressure, and water can be selected as the source of hydrogen, which has attracted widespread attention from scientific workers. However, so far, the reported electrocatalysts have low ammonia production rates in nitrogen electrochemical reduction reactions, making it difficult to meet industrial needs. Therefore, developing electrocatalysts that can efficiently electrochemically reduce nitrogen to synthesize ammonia is a very challenging task. In response to this problem, the researchers chose a metal-organic framework (ZIF-8) as the matrix, and controlled the existence form of ruthenium in the metal-organic framework by adding ruthenium-based compounds to the reaction precursor. The researchers found that when less ruthenium-based compounds were added, highly dispersed nitrogen-coordinated ruthenium single-atom catalysts (Ru SAs/NCs) could be obtained. After increasing the input amount of ruthenium-based compounds, ruthenium will be dispersed in the metal organic framework (Ru NPs/NC) in the form of small particles. Subsequently, the researchers applied these two catalysts to the nitrogen electrochemical reduction reaction and found that the Ru SAs/NC catalyst could efficiently electrocatalytically reduce nitrogen to synthesize ammonia at a voltage of -0.2V relative to the standard hydrogen electrode. The ammonia production rate was as high as 120.9 μgNH3mg-1cat.h-1, and the ammonia production rate was 1.98 times that of Ru NPs/NC. Experimental and theoretical calculation studies further revealed that the high-efficiency catalytic performance of nitrogen-coordinated ruthenium single-atom catalysts mainly comes from the efficient dissociation of nitrogen molecules by the single-atom catalysts. This research work not only opens up a new way for single-atom catalysts to be used in electrochemical ammonia synthesis reactions, but also further advances the possibility of electrochemical ammonia synthesis in practical applications. This research was supported by the Key Frontier Science Research Project of the Chinese Academy of Sciences, the Ministry of Science and Technology, * * Funded by the Natural Science Foundation of China and the Anhui Provincial Key Research and Development Program.