Atomic‐Level Design of Acid–Base Pairs in Oxides for Selective Catalytic Reduction of Nitrogen Oxides with Ammonia

Abstract

Abstract Selective catalytic reduction of nitrogen oxides (NO x ) with NH 3 (NH 3 ‐SCR) poses considerable potential in the abatement of NO x 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‐O v ‐W acid–base pairs through constructing oxygen vacancies on Ce/WO x , thereby fostering SCR activity. Experimental and theoretical results reveal that Ce‐O v ‐W acid–base pairs not only provide more Ce 3+ sites for promoting the reactivity of adsorbed NO, but also accelerate the reaction between NH 3 and gaseous NO owing to the generation of W 5+ species with superior surface acidity, which enhance Langmuir–Hinshelwood and Eley–Rideal mechanisms, respectively. Consequently, the designed catalysts achieve over 90% NO x conversion above 250 °C and exhibit higher activity than normal Ce/WO 3 and V/W‐TiO 2 commercial catalysts, with anti‐poisoning of SO 2 and H 2 O under harsh working conditions, expecting to provide the guidance for promoting de‐NO x industrial application.