Enhancing Ozone Decomposition in Humid Environments through Carbon Doping to Disrupt the Hydrogen Bond Network in Mullite YMn2O5

Environ Sci Technol. 2024 Nov 19;58(46):20687-20698. doi: 10.1021/acs.est.4c05653. Epub 2024 Nov 6.

Abstract

The strong adsorption of water molecules at the active site of the catalyst presents significant challenges in ozone decomposition, particularly at room temperature and in humid environments. To address this issue, we doped carbon atoms into the Mn-mullite YMn2O5 catalyst to replace oxygen, resulting in efficient and stable ozone decomposition under highly humid conditions. Utilizing DFT calculations, our study demonstrated that carbon doping disrupts hydrogen bond networks on the catalyst surface, thereby reducing water adsorption. Furthermore, carbon doping regulated the electronic structure of active sites, fundamentally reversing the adsorption strength of water and ozone molecules, which avoids the decline in catalytic activity caused by competitive water adsorption. Experimentally, under room temperature and relative humidity (RH) 50%, the carbon-doped YMn2O5 catalyst maintained 100% conversion in decomposing 100 ppm of ozone for at least 24 h, surpassing the most reported catalysts against water poisoning. Furthermore, the utilization of a carbon-doped mullite-loaded air cleaner demonstrated promising application in degrading ozone. The approach of enhancing catalyst water resistance through carbon doping, which disrupts hydrogen bonds, provided valuable insights into the design of stable and efficient room-temperature ozonolysis catalysts.

Keywords: carbon doping; hydrogen bond network; mullite catalyst; ozone decomposition; water resistance.

MeSH terms

  • Adsorption
  • Carbon* / chemistry
  • Catalysis
  • Humidity
  • Hydrogen Bonding*
  • Ozone* / chemistry

Substances

  • Ozone
  • Carbon