Exceptional Ozone Decomposition over δ-MnO<sub>2</sub>/AC under an Entire Humidity Environment
Wenjing Dai, Boge Zhang, Jian Ji, Biyuan Liu, Ruijie Xie, Yanling Gan, Xiaowen Xie, Jiarui Zhang, Pingli Huang, Haibao Huang
Abstract
Ozone (O 3 ) 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 O 3 elimination, while the moisture-induced low stability represents the major challenge for its practical applications. Here, activated carbon (AC) supported δ-MnO 2 (Mn/AC-A) was facilely synthesized via mild redox in an oxidizing atmosphere to obtain exceptional O 3 decomposition capacity. The optimal 5Mn/AC-A achieved nearly 100% of O 3 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-MnO 2 . Density functional theory (DFT) calculations confirmed that the abundant oxygen vacancies and a low desorption energy of intermediate peroxide (O 2 2– ) can significantly boost O 3 decomposition activity. Moreover, a kilo-scale 5Mn/AC-A with low cost (∼1.5 $/kg) was used for the O 3 decomposition in practical applications, which could quickly decompose O 3 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 O 3 elimination.