Jump to main content
Jump to site search


Unraveling the mechanisms of room-temperature catalytic degradation of indoor formaldehyde and its biocompatibility on colloidal TiO2-supported MnOx–CeO2

Author affiliations

Abstract

This work overcomes the limitations in room-temperature and moisture-dependent activity of transition metal oxide-based catalysts for sub-ppm formaldehyde removal. The active site exposure and self-assembly hydrophilicity were highlighted in MnOx–CeO2 (MCO) nanospheres after the loading of colloidal 2.1 wt% TiO2 particles (TO–MCO). Approximately 57% (relative humidity = 72%) and 41% (dry air) recycling catalytic activities at 35 °C were achieved. Our results proved that surface electron transfer, which was previously weakened because of the loss of surface oxygen species and unsuitable defect-site depositions of low active ions, in the MCO catalyst was recovered via the dispersion of hydrophilic Ti–O groups. This electron transfer was also strongly correlated with the specific surface area, porosity, and oxidation states of transition metals. The greater active site exposure derived from the cyclic electron transfer eventually enhanced the HCHO chemisorption and participation of oxygen species on the surface of TO–MCO throughout the bimetallic (Mn–Ce) dismutation reactions. The abundant superoxide radicals that were activated by these oxygen species prompted a nucleophilic attack on carbonyl bonds. Direct photoionization mass spectrometry determined formic acid, dioxirane (minor), and HOCH2OOH (little) as intermediates governing the HCHO selectivity to CO2. The cytotoxicity of catalysts exposed to yeast cells was evaluated for their potential environmentally friendly application indoors.

Graphical abstract: Unraveling the mechanisms of room-temperature catalytic degradation of indoor formaldehyde and its biocompatibility on colloidal TiO2-supported MnOx–CeO2

Back to tab navigation

Supplementary files

Publication details

The article was received on 09 Feb 2018, accepted on 08 Mar 2018 and first published on 15 Mar 2018


Article type: Paper
DOI: 10.1039/C8EN00176F
Citation: Environ. Sci.: Nano, 2018, Advance Article
  •   Request permissions

    Unraveling the mechanisms of room-temperature catalytic degradation of indoor formaldehyde and its biocompatibility on colloidal TiO2-supported MnOx–CeO2

    H. Li, T. Huang, Y. Lu, L. Cui, Z. Wang, C. Zhang, S. Lee, Y. Huang, J. Cao and W. Ho, Environ. Sci.: Nano, 2018, Advance Article , DOI: 10.1039/C8EN00176F

Search articles by author

Spotlight

Advertisements