Tailoring oxygen vacancies in ZSM-5@MnOx catalysts for efficient oxidation of benzyl alcohol

Oxygen vacancy (OV) plays a significant role in the catalytic performance of oxidation catalysts. Herein, [email protected]x catalyst with abundant OVs was firstly prepared by in-situ growth method. The prepared catalyst exhibits good catalytic activity for the selective oxidation of benzyl alcohol (BA) to benzaldehyde (BAD) with ~100% BA conversion and ~100% BAD selectivity within 3 h. We have proved that the OV in [email protected]x catalyst is the main active site for the BA oxidation. Besides, the OV formation mechanism is proposed based on the influences of modified ZSM-5 supports on OVs. Results show that sodium ions in ZSM-5 are conducive to enhancing the coating of MnOx on supports, and protons in ZSM-5 are beneficial for the formation of OVs by dehydrating with hydroxyls on MnOx. Based on the mechanism, we further enrich OVs by the deep dehydration to improve its catalytic performance. This work provides a novel route for the design of OVs in the [email protected]x catalyst.