Breaking the Humidity Barrier in Ozone Decomposition: Dual-Engineered Mn–Co Catalyst with Vacancy-Orbital Synergy

Ground-level ozone poses significant health risks in indoor environments. However, conventional manganese-based catalysts suffer from rapid deactivation under humid conditions caused by competitive water adsorption and the occupation of active sites by the O 2 2– intermediates. The atomic-level design of Mn 3+ /Co 2+ sites integrates vacancy defect engineering with heterometallic orbital coupling, overcoming the humidity-induced deactivation bottleneck in ozone catalysis. In situ spectra and theoretical calculations confirm that this dual-engineering strategy alters the surface electronic configuration, weakens water adsorption energy, and accelerates O 2 2– dissociation through a low-energy-barrier pathway. Remarkably, this self-sustaining catalyst requires no auxiliary energy (heat or light), allowing seamless integration into air purification systems via simple coating techniques. This innovation opens new possibilities for combating indoor ozone pollution in energy-efficient manner, maintaining stable efficiency (at least 100 h) under realistic humid conditions (25 °C, 4 vol % H 2 O).