Alkali-Resistant Catalytic Reduction of NOx by Using Ce–O–B Alkali-Capture Sites

Reducing the poisoning effect arising from alkali metals over catalysts for selective catalytic reduction (SCR) of NO_x by NH₃ is still an urgent issue to be solved. Herein, alkali-resistant NO_x reduction over B-doped CeO₂/TiO₂ catalysts (Ce-B/TiO₂) with Ce-O-B alkali-capture sites was originally demonstrated. It was noted that boron was confirmed to be doped into the lattice of CeO₂ to form the Ce-O-B structure. In this way, more active Ce(III) species and oxygen vacancies were generated from B-doped CeO₂, thus accelerating the redox cycle and enhancing the adsorption/activation of NO. Gratifyingly, the created Ce-O-B sites as alkali-capture sites could be effectively combined with K and release the poisoned Ce active sites, which maintained efficient NH₃ and NO adsorption/activation over K poisoned Ce-B/TiO₂. This work paves a way for designing highly efficient and alkali-resistant SCR catalysts in both academic and industrial fields.