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 NOx by NH3 is still an urgent issue to be solved. Herein, alkali-resistant NOx 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.