Exceptional Ozone Decomposition over δ-MnO₂/AC under an Entire Humidity Environment

Ozone (O₃) pollution is highly detrimental to human health and the ecosystem due to it being ubiquitous in ambient air and industrial processes. Catalytic decomposition is the most efficient technology for O₃ elimination, while the moisture-induced low stability represents the major challenge for its practical applications. Here, activated carbon (AC) supported δ-MnO₂ (Mn/AC-A) was facilely synthesized via mild redox in an oxidizing atmosphere to obtain exceptional O₃ decomposition capacity. The optimal 5Mn/AC-A achieved nearly 100% of O₃ decomposition at a high space velocity (1200 L g^-1 h^-1) and remained extremely stable under entire humidity conditions. The functionalized AC provided well-designed protection sites to inhibit the accumulation of water on δ-MnO₂. Density functional theory (DFT) calculations confirmed that the abundant oxygen vacancies and a low desorption energy of intermediate peroxide (O₂^2-) can significantly boost O₃ decomposition activity. Moreover, a kilo-scale 5Mn/AC-A with low cost (∼1.5 $/kg) was used for the O₃ decomposition in practical applications, which could quickly decompose O₃ pollution to a safety level below 100 μg m^-3. This work offers a simple strategy for the development of moisture-resistant and inexpensive catalysts and greatly promotes the practical application of ambient O₃ elimination.