Hollow MnO2 architectures exhibit enhanced catalytic performance for volatile organic compound removal

Tackling the urgent need for efficient catalytic abatement of harmful volatile organic compounds (VOCs), this study presents the controlled synthesis of hollow MnO 2 microcuboids with hierarchical structures for enhanced benzene oxidation catalysis. The hollow MnO 2 catalysts, obtained via a redox reaction between MnCO 3 precursors and KMnO 4 followed by selective acid etching, exhibit significantly higher surface area, oxygen defects, and Mn 3+ concentration compared to solid MnO 2 . Comprehensive characterization techniques reveal the structure–activity relationships governing the superior catalytic performance, which rivals that of a 1 % Pt/Al 2 O 3 reference catalyst. The unique hollow morphology, comprising thin shell walls built from interconnected nanorods, substantially enhances active site accessibility and lowers the activation energy barrier. A key feature of the hollow structure is its ability to concentrate reactants within the confined internal void through capillary action, a phenomenon that enriches reactant concentrations and further promotes catalytic activity. In-situ DRIFTS analyses provide mechanistic insights into surface species transformations during benzene oxidation. Notably, the hollow MnO 2 catalyst demonstrates impressive long-term stability and high activity in the presence of water vapor, highlighting its potential for practical industrial VOC abatement applications.