Highly efficient degradation of sulfur-containing volatile organic compounds by amorphous MnO2 at room temperature: Implications for controlling odor pollutants.

Sulfur-Containing Volatile Organic Compounds (S-VOCs) are notorious for global air pollution due to their odorous characteristics and exhibiting adverse health effects. Nevertheless, the catalytic degradation of S-VOCs at low temperatures is still a tremendous challenge for air purification. In this study, methyl mercaptan (CH 3 SH), a typical S-VOCs contaminant, could be completely removed by amorphous MnO 2 with high efficiency (100 %) for 40 h at room temperature, and demonstrating significantly enhanced stability (over 100 h) in the presence of 20 %RH (Relative humidity), which is far superior to the performance of previous reported catalysts. The amorphous MnO 2 with surface-rich oxygen vacancies can trigger the formation of more reactive oxygen species (ROS) and stronger O 2 adsorption capability comparing with the crystalline MnO 2 , the corresponding results are characterized by XPS and EPR. Moreover, In Situ- DRIFTS coupled with DFT calculations revealed that the CH 3 SH could be transformed into CO 3 2-/SO 4 2- by ROS. Unexpectedly, the amorphous MnO 2 also displayed excellent activity and stability towards to other typical S-VOCs, which is beneficial for the actual industrial application. The findings can provide novel insights into the design of highly efficient and stable catalysts to eliminate odor gaseous pollutants over a broad operating concentration window at room temperature. [Display omitted] • CH 3 SH could be completely removed by amorphous MnO 2 at room temperature for the first time. • Abundant Mn defects at amorphous MnO 2 interface are favorable for CH 3 SH conversion • A complete CH 3 SH conversion path on amorphous MnO 2 surface is proposed. • In Situ- DRIFTS and DFT calculations confirm that CH 3 SH could be transformed into CO 3 2-/SO 4 2- by ROS. • the amorphous MnO 2 also displayed excellent activity and stability towards to other typical S-VOCs. [ABSTRACT FROM AUTHOR]