Excellent catalysts with low-temperature activity and relatively wide temperature window for selective catalytic reduction of NO with ammonia(NH_(3)-SCR) are highly demanded in view of the practical treatment of NO.He...Excellent catalysts with low-temperature activity and relatively wide temperature window for selective catalytic reduction of NO with ammonia(NH_(3)-SCR) are highly demanded in view of the practical treatment of NO.Herein,we have designed a highly active VOx-MnOx/CeO_(2) material based on the intrinsic requirement of SCR reaction for catalyst,namely redox sites and surface acid sites.The vanadium oxide and manganese oxide are highly dispersed over the ceria mesosphere via simple incipient wetness impregnation.The loading of manganese could introduce acid sites and enhance the redox property remarkably,while the loading of vanadium increases acid sites and weakens redox property.Through tentatively controlling the appropriate loading ratio of the two components,the optimal catalyst achieves a balance between redox property and surface acidity.The work shed light on the development of new SCR catalyst with superior low temperature activity,wide work temperature window and good hydrothermal stability.展开更多
CeO2 is an important porous material with a wide range of applications in the abatement of volatile organic compounds （VOCs）. In this paper, we prepared a series of novel three-dimensional （3D） micro/nanostructure...CeO2 is an important porous material with a wide range of applications in the abatement of volatile organic compounds （VOCs）. In this paper, we prepared a series of novel three-dimensional （3D） micro/nanostructured CeO2 materials via a solvothermal method. Organic acid-assisted synthesis and inorganic acid post-treatment were used to adjust the Ce02 microstructures. The size of the 3D micro/nanostructures could be controlled in the range from 180nm to 1.5 μm and the surface morphology changed from rough to smooth with the use of different organic acids. The CeO2 synthesized with acetic acid featured a hierarchical porosity and showed good performance for toluene catalytic combustion： a T50 of 187 ℃ and a T90 of 195 ℃. Moreover, the crystallite size, textural properties, and surface chemical states could be tuned by inorganic acid modification. After treatment with HNO3, the modified CeO2 materials exhibited improved catalytic activity, with a T50 of-175 ℃ and a T90 of -187 ℃. We concluded that the toluene combustion activity is related to the porosity and the amount of surface active oxygen of the CeO2. Both these features can be tuned by the co-work of organic and inorganic acids.展开更多
基金Project supported by the National Natural Science Foundation of China (21576054)Science and Technology Planning of Guangdong Province (2016B020241003)+1 种基金Natural Science Foundation of Guangdong Province(2018A030310563)Foundation of Higher Education of Guangdong Province(2018KZDXM031)。
文摘Excellent catalysts with low-temperature activity and relatively wide temperature window for selective catalytic reduction of NO with ammonia(NH_(3)-SCR) are highly demanded in view of the practical treatment of NO.Herein,we have designed a highly active VOx-MnOx/CeO_(2) material based on the intrinsic requirement of SCR reaction for catalyst,namely redox sites and surface acid sites.The vanadium oxide and manganese oxide are highly dispersed over the ceria mesosphere via simple incipient wetness impregnation.The loading of manganese could introduce acid sites and enhance the redox property remarkably,while the loading of vanadium increases acid sites and weakens redox property.Through tentatively controlling the appropriate loading ratio of the two components,the optimal catalyst achieves a balance between redox property and surface acidity.The work shed light on the development of new SCR catalyst with superior low temperature activity,wide work temperature window and good hydrothermal stability.
基金This work was financially supported by the Natural Science Foundation of China （21576054）, the Scientific Project of Guangdong Province （2014A010106030, 2016A010104017,2016B020241003）, and the Foundation of Higher Education of Guangdong Province （201 SICFSCX027） of China.
文摘CeO2 is an important porous material with a wide range of applications in the abatement of volatile organic compounds （VOCs）. In this paper, we prepared a series of novel three-dimensional （3D） micro/nanostructured CeO2 materials via a solvothermal method. Organic acid-assisted synthesis and inorganic acid post-treatment were used to adjust the Ce02 microstructures. The size of the 3D micro/nanostructures could be controlled in the range from 180nm to 1.5 μm and the surface morphology changed from rough to smooth with the use of different organic acids. The CeO2 synthesized with acetic acid featured a hierarchical porosity and showed good performance for toluene catalytic combustion： a T50 of 187 ℃ and a T90 of 195 ℃. Moreover, the crystallite size, textural properties, and surface chemical states could be tuned by inorganic acid modification. After treatment with HNO3, the modified CeO2 materials exhibited improved catalytic activity, with a T50 of-175 ℃ and a T90 of -187 ℃. We concluded that the toluene combustion activity is related to the porosity and the amount of surface active oxygen of the CeO2. Both these features can be tuned by the co-work of organic and inorganic acids.
