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A series of V-Ce(SO 4 ) 2 /Ti catalysts for selective catalytic reduction (SCR) of NO with ammonia are prepared by impregnation method. Low temperature SCR activity and alkali resistance of the optimal V-0.5Ce(SO 4 ) 2 /Ti sample are found to be better than on the commercial V-W/Ti catalyst. Also, V-0.5Ce(SO 4 ) 2 /Ti shows an excellent durability in the presence of SO 2 and H 2 O, indicating to have prospects for the industrial application. Based on catalysts characterization and in-situ DRIFTS studies, a higher proportion of surface active oxygen generated by the introduction of Ce and a much faster H 2 reduction point out the improved redox properties of V-0.5Ce(SO 4 ) 2 /Ti, which results in a stronger NO oxidative activation and is confirmed by a more abundant formation of surface NO + and NO 3 − species. When exposed to SCR conditions where both NH 3 and NO are present, this enhanced NO activation can produce more reactive nitrite and/or NO + intermediates which then readily react with adsorbed NH 3 and decompose to N 2 and H 2 O, accounting for the improved SCR activity of V-0.5Ce(SO 4 ) 2 /Ti at low temperatures. The addition of Ce(SO 4 ) 2 also provides abundant reactive acid sites and adsorbed NH 3 species thus increase. Even after Na poisoning, adequate surface acidity and redox properties still remain. Furthermore, relatively higher contents of V-OH are preserved owing to the interaction between Na and O S O, acting as a protection for the active sites. These promotional effects contribute to the better alkali resistance of V-0.5Ce(SO 4 ) 2 /Ti. Therefore, all the results suggest that V-0.5Ce(SO 4 ) 2 /Ti is a promising candidate as a catalyst for NH 3 -SCR in coal-fired power plants, especially under high Na-content conditions. [ABSTRACT FROM AUTHOR]