Effect of Organic Reagents on the Phase Structure of MnOx Porous Nanospheres: Catalytic Oxidation of Methanol at Low Temperatures.

Three porous nanosphere-structured manganese oxide (MnOx) catalysts were prepared and used for the low-temperature catalytic oxidation of methanol using different organic reagents as structure-directing agents to modulate the surface morphology of the catalysts. The structure-effect relationship between MnOx catalysts with different microsphere structures and the catalytic oxidation activity of methanol were analyzed using various characterization techniques. The MnOx–J catalyst had significantly higher catalytic oxidation activity for methanol (T90 = 130 °C) than the other MnOx catalysts. The characterization results indicate that the regulation of 2-methylimidazole promotes the formation of structural defects, surface-adsorbed oxygen, and Mn3+ on the surface of the manganese-based catalysts and enhances the low-temperature reduction capacity of the catalysts—the primary reason for the high reactivity of the MnOx–J samples. Three MnOx catalysts with porous nanosphere structures were synthesized using different organic reagents as structure-directing agents. Among them, the 2-methylimidazole organo-reagent promoted the formation of structural defects, surface adsorbed oxygen and Mn3+ on the surface of the manganese-based catalysts, thus enhancing the catalytic oxidation activity of the catalysts in low-temperature methanol-catalyzed reactions. [ABSTRACT FROM AUTHOR]