The interaction between cobalt oxide nanospheres and low-loaded silver and its effects on soot oxidation
WANG Jing1, HE Wenyu1, HE Xinyang1, CHEN Longwen1,ZHANG Jun1, FU Mingli1, 2, 3*, YE Daiqi1, 2, 3
(1 School of Environment and Energy, South China University of Technology, Guangzhou 510006， Guangdong, China；2 Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control,Guangzhou 510006， Guangdong, China；3 National Engineering Laboratory of Volatile Organic Pollution Control Technology and Equipment, Guangzhou 510006， Guangdong, China)
Abstract:
In this paper, nano-spherical cobalt oxide and manganese oxide supports were synthesized by hydrothermal method, and the Ag/Co3O4 and Ag/Mn2O3 catalysts with low silver loading (0.9%~1.5%，mass fraction) were prepared by impregnation method. Under tight contact conditions, the T10，T50 and T90 values of Ag/Co3O4 were 250 ℃, 284 ℃ and 311 ℃, showing excellent catalytic activity for soot oxidation. The prepared catalysts were characterized by XRD, H2-TPR, TG, EPR, XPS and other techniques. The results showed that when Ag was introduced into cobalt oxide and manganese oxide, respectively, Ag/Co3O4 exhibited better soot combustion performance. This is due to the stronger metal-support interaction between Ag and Co3O4, which creates more Co3+ species and appropriate oxygen vacancies on Ag/Co3O4, increases the surface active oxygen numbers and the oxygen mobility, and effectively improves the ability of Ag/Co3O4 to oxidize soot. In addition, the metallic properties of Ag and the nano-spherical morphology of the catalysts are also conducive to the catalytic oxidation of soot.
KeyWords:
soot; Ag; cobalt oxide; catalytic combustion; metal-support interaction
