Optimizing cooperative catalysis of multiple defective interfaces in Pt/ mullite catalysts for NO oxidation

Nitric oxide (NO) oxidation is an integral part of the nitrogen chemical cycle, but competitive activation of NO/O-2 over single platinum (Pt)-based catalysts result in inadequate low temperature performance. Here, we constructed catalysts with BiMn2O5/CeO2 and Pt/BiMn2O5 defective interfaces (sufficient activation of NO/O-2). The constructed catalyst achieved 95 % NO conversion at 260 degrees C in NO/O-2 atmosphere, superior to most known catalysts. Even after aging (800 degrees C for 16 h), the NO conversion was up to 76 %. Further, the catalyst can be applied to actual diesel exhaust. Detailed oxygen vacancies (O-v) characterization reveals that BiMn2O5/CeO2 defective interface created by Ce3+-O-v + Mn4+-O <-> Ce4+-O + Mn3+-O-v promote the activation of NO (on Mn3+ sites) and O-2 (on Mn3+-O-v sites). Besides, the O-v on Pt/BiMn2O5 defective interface compensate for the loss of Pt sites ensuring hydrothermal stability. And this construction of multiple defective interfaces develops a pathway for boosting catalytic reactions.