Atomic‐level design of acid‐base pairs in oxides for selective catalytic reduction of nitrogen oxides with ammonia

Selective catalytic reduction of nitrogen oxides (NOx) with NH3 (NH3‐SCR) poses considerable potential in the abatement of NOx emissions. However, the efficient adsorption and speedy reaction of reactants following the specific mechanism in a favorable way is still a challenge for enhancing catalysis. Herein, we propose the strategy aimed at adjusting electronic properties of Ce‐Ov‐W acid‐base pairs through constructing oxygen vacancies on Ce/WOx, thereby fostering SCR activity. Experimental and theoretical results reveal that Ce‐Ov‐W acid‐base pairs not only provide more Ce3+ sites for promoting the reactivity of adsorbed NO, but also accelerate the reaction between NH3 and gaseous NO owing to the generation of W5+ species with superior surface acidity, which enhance Langmuir‐Hinshelwood and Eley‐Rideal mechanisms, respectively. Consequently, the designed catalysts achieve over 90% NOx conversion above 250°C and exhibit higher activity than normal Ce/WO3 and V/W‐TiO2 commercial catalysts, with anti‐poisoning of SO2 and H2O under harsh working conditions, expecting to provide the guidance for promoting de‐NOx industrial application.