Compared with conventional catalysts, single-atom catalysts (SACs) exhibit many superior properties, including high catalytic activity, high adsorption selectivity and high metal atom utilization. SACs show excellent performance in fuel cells, electrocatalytic reduction of CO2, and hydrogenolysis. Similarly, SACs exhibit excellent properties in the field of catalytic oxidation: FeSA shows high catalytic activity for the catalysis of benzene, methane, and mercury 30 at room temperature.