▎ 摘　　要

NOVELTY - Preparing single-atom catalyst, comprises either adding manganese precursor into solvent and stirring to dissolve, adding solution A into carrier powder by equal volume impregnation method, and drying, and calcining to obtain final product; or adding the manganese precursor into the solvent and stirring to dissolve, adding solution A into carrier powder by excessive impregnation method, stirring, and then suction filtering, drying filter cake, and calcining to obtain final product; or adding the manganese precursor into the solvent and stirring to dissolve, and using a water bath to heat the solution A, adding carrier powder into solution A by sedimentation and precipitation method under stirring, and continuing stirring, dropwise adding alkaline solution into mixed solution B to adjust the pH, stirring and suction filtering, drying the filter cake, and calcining to obtain final product. USE - The single-atom catalyst is useful in synthesizing methacrylonitrile (claimed). ADVANTAGE - The single-atom catalyst: realizes low manganese loading of less than 1 wt.%; has 100% atomic utilization, and excellent catalytic performance and reaction stability; can quickly catalyze the synthesis of methacrylonitrile; reaches the product yield of methacrylonitrile up to 99%; and reduces the cost of manganese raw materials. DETAILED DESCRIPTION - Preparing single-atom catalyst, comprises either adding manganese precursor into solvent and stirring to dissolve to obtain solution A, adding the solution A into carrier powder by equal volume impregnation method, and drying at room temperature for 2-24 hours, then drying at 60-150 ℃ for 2-24 hours, and calcining at 300-600 ℃ for 2-72 hours under air or oxygen atmosphere to obtain final product; or adding the manganese precursor into the solvent and stirring to dissolve to obtain solution A, adding the solution A into carrier powder by excessive impregnation method, stirring at room temperature for 6-24 hours, and then suction filtering to obtain a filter cake, drying the filter cake at 60-150 ℃ for 2-24 hours, and calcining at 300-600 ℃ for 2-72 hours under air or oxygen atmosphere to obtain final product; or adding the manganese precursor into the solvent and stirring to dissolve to obtain solution A, and using a water bath to heat the solution A at 40-80 ℃, adding carrier powder into solution A by sedimentation and precipitation method under stirring, and continuing stirring for 1-4 hours to obtain mixed solution B, dropwise adding alkaline solution into the mixed solution B to adjust the pH to 9-10, stirring for 1-4 hours and then suction filtering to obtain filter cake, drying the filter cake at 60-150 ℃ for 2-24 hours, and calcining at 300-600 ℃ for 2-72 hours under air or oxygen atmosphere to obtain final product. An INDEPENDENT CLAIM is also included for single-atom catalyst prepared by above method.