论文名称：Investigation into the Catalytic Roles of Various Oxygen Species over Different Crystal Phases of MnO2 for C6H6 and HCHO Oxidation
论文类型：期刊论文
发表刊物：ACS CATALYSIS
收录刊物：SCIE
卷号：10
期号：11
页面范围：6176-6187
ISSN号：2155-5435
关键字：manganese oxides; oxygen species; C6H6 and HCHO; catalytic oxidation; MVK mechanism
摘要：Although manganese oxide (MnO2) exhibits excellent activity in various oxidation reactions, especially for volatile organic compound oxidation, the origin of the catalytic activity remains ambiguous and controversial. In this study, four types of MnO2 catalysts with crystal phases corresponding to alpha-, beta-,gamma-, and delta-MnO2 were synthesized, and their catalytic properties in HCHO and C6H6 oxidation were studied. alpha- and gamma-MnO2 were found to possess much better activity for C6H6 oxidation than delta- and beta-MnO2 catalysts, whereas delta-MnO2 exhibited the best performance for HCHO oxidation as compared with other types of MnO2. Three kinds of oxygen species were discriminated based on their Mn-O bond strength and reducibility. By quantitatively correlating the amount of specific oxygen species with the reaction rates, the catalytic roles of different oxygen species in HCHO and C6H6 oxidation were clarified. With the assistance of isotopic labeling studies, the participation of oxygen species in C6H6 oxidation-which followed a Mars-van Krevelen mechanism-was illuminated.
发表时间：2020-06-05