irritation to human beings.The removal of hexanal has rarely been investigated.In this study,we found that the amount of Mn vacancies inγ-MnOOH significantly affects its catalytic activity toward hexanal degradation ...irritation to human beings.The removal of hexanal has rarely been investigated.In this study,we found that the amount of Mn vacancies inγ-MnOOH significantly affects its catalytic activity toward hexanal degradation and transformation into CO2.The as-synthesized Mn vacancy-richγ-MnOOH exhibited high efficiency toward hexanal removal,achieving 100%degradation of 15 ppm hexanal at 85℃ and complete transformation into CO2 at 160 ℃ under the gas hourly space velocity of 240 L/(g·h);its activity could be completely regenerated by in-situ heat treatment at 180°C.Moreover,it was found that the degradation of hexanal occurred in a stepwise manner,i.e.,losing one CH2 unit per step.Electron spinning resonance studies detected strong indicative signals for the presence of the superoxide anion radical(?O2^–)on Mn-vacancy-richγ-MnOOH,which may act as active oxygen species for the hexanal degradation.Understanding the role of Mn-vacancy and the mechanism of hexanal degradation byγ-MnOOH are essential for developing efficient oxide catalysts for volatile organic compounds besides hexanal.展开更多
基金supported by National Natural Science Foundation of China (21677083)Suzhou-Tsinghua Innovation Guiding Program (2016SZ0104)~~
文摘irritation to human beings.The removal of hexanal has rarely been investigated.In this study,we found that the amount of Mn vacancies inγ-MnOOH significantly affects its catalytic activity toward hexanal degradation and transformation into CO2.The as-synthesized Mn vacancy-richγ-MnOOH exhibited high efficiency toward hexanal removal,achieving 100%degradation of 15 ppm hexanal at 85℃ and complete transformation into CO2 at 160 ℃ under the gas hourly space velocity of 240 L/(g·h);its activity could be completely regenerated by in-situ heat treatment at 180°C.Moreover,it was found that the degradation of hexanal occurred in a stepwise manner,i.e.,losing one CH2 unit per step.Electron spinning resonance studies detected strong indicative signals for the presence of the superoxide anion radical(?O2^–)on Mn-vacancy-richγ-MnOOH,which may act as active oxygen species for the hexanal degradation.Understanding the role of Mn-vacancy and the mechanism of hexanal degradation byγ-MnOOH are essential for developing efficient oxide catalysts for volatile organic compounds besides hexanal.
