Gasoline soot particles pose a severe threat to the ecological environment and human health,but they can be potentially filtered out by using catalytic gasoline particulate filter(cGPF),whose core component is a catal...Gasoline soot particles pose a severe threat to the ecological environment and human health,but they can be potentially filtered out by using catalytic gasoline particulate filter(cGPF),whose core component is a catalyst coating.To develop more effective catalyst coatings with excellent activity,stability,and water resistance,a kind of composite oxide MnO_(x)/CeO_(2)-ZrO_(2) was synthesized using different methods,and its soot oxidation performance was evaluated under low O_(2) concentrations.Herein,MnO_(x)/CeO_(2)-ZrO_(2) prepared by impregnation(abbreviated as MCZ-IM)exhibits a T_(50)(temperature required for 50% soot conversion)of 329℃in 1%O_(2) and 370℃ in 0.5%O_(2),displaying better comprehensive performance when compared to catalysts prepared by high-energy ball milling(abbreviated as MCZ-HB)and co-precipitation(abbreviated as MCZ-CP).Structure-activity relationship reveals that soot oxidation under low O_(2) concentrations is weakly correlated with textural and structural properties,but strongly depends on the generation and migration of active oxygen species(AOS),especially superoxide(O_(2)^(-))and peroxide(O_(2)^(2-))anions,which are linked to redox properties,oxygen storage and release capacity,as well as amount of oxygen vacancies.The impregnation method enhances oxygen species adsorption,activation and desorption more effectively,endowing it with a more effective approach to enhancing AOS generation and mobility.Therefore,this study not only provides a preparation strategy for particulate matter oxidation catalysts applicable to actual operating conditions,but also offers insights into the migration of AOS at low O_(2) concentrations.展开更多
基金Advanced Materials-National Science and Technology Major Project(2024ZD0606500)National Natural Science Foundation of China(21902110)Sichuan Provincial Science Foundation(2023NSFSC0093)。
文摘Gasoline soot particles pose a severe threat to the ecological environment and human health,but they can be potentially filtered out by using catalytic gasoline particulate filter(cGPF),whose core component is a catalyst coating.To develop more effective catalyst coatings with excellent activity,stability,and water resistance,a kind of composite oxide MnO_(x)/CeO_(2)-ZrO_(2) was synthesized using different methods,and its soot oxidation performance was evaluated under low O_(2) concentrations.Herein,MnO_(x)/CeO_(2)-ZrO_(2) prepared by impregnation(abbreviated as MCZ-IM)exhibits a T_(50)(temperature required for 50% soot conversion)of 329℃in 1%O_(2) and 370℃ in 0.5%O_(2),displaying better comprehensive performance when compared to catalysts prepared by high-energy ball milling(abbreviated as MCZ-HB)and co-precipitation(abbreviated as MCZ-CP).Structure-activity relationship reveals that soot oxidation under low O_(2) concentrations is weakly correlated with textural and structural properties,but strongly depends on the generation and migration of active oxygen species(AOS),especially superoxide(O_(2)^(-))and peroxide(O_(2)^(2-))anions,which are linked to redox properties,oxygen storage and release capacity,as well as amount of oxygen vacancies.The impregnation method enhances oxygen species adsorption,activation and desorption more effectively,endowing it with a more effective approach to enhancing AOS generation and mobility.Therefore,this study not only provides a preparation strategy for particulate matter oxidation catalysts applicable to actual operating conditions,but also offers insights into the migration of AOS at low O_(2) concentrations.
