Accelerated activation of ozone on Fe-doped MnO₂ for highly efficient ozone catalytic oxidation of ethyl acetate

Ozone catalytic oxidation (OCO) is a promising technology for controlling malodorous pollution, effectively removing low-concentration oxygenated volatile organic compounds (OVOCs) at low temperatures. However, the catalytic performance of manganese oxides remains constrained by insufficient reactive oxygen species (ROS) and high humidity, particularly at low temperatures. To address this, a series of MMnO₂ catalysts were successfully prepared by introducing highly dispersed transition metals (M = Fe, Ce, Mo) into MnO₂ via an in-situ hydrothermal method, aiming to improve low-temperature performance. Among these catalysts, the FeMnO₂ catalyst exhibited the highest catalytic performance, achieving 100 % conversion of 30 ppm ethyl acetate (EA) and a 92.78 % mineralization rate at 70 °C, along with exceptional stability and water resistance (12.8 vol.%). In situ characterization techniques have demonstrated that the introduction of Fe significantly weakens the Mn-O bond in MnO₂. The formation of abundant oxygen vacancies facilitates the adsorption and activation of O₃. Both ¹O₂ and •O₂^- species serve as crucial ROS, promoting the effective mineralization of EA on the catalyst surface and reducing the generation of reaction intermediates. This study provides a significant foundation for the further development of catalysts targeting low-concentration OVOCs and for enhancing the practical low-temperature catalytic activity of transition metal oxides.