Impact Factor:24.319
DOI number:10.1016/j.apcatb.2021.120118
Journal:Applied Catalysis B: Environmental
Key Words:Photo-oxidation of VOC mixtures；Pd cocatalyst，Formaldehyde，toluene and xylenes；Toxic intermediates；Oxygen activation
Abstract:Photocatalytic removal of single volatile organic compounds (VOCs) has been widely investigated; however, photodecomposition of VOC mixtures has been rarely addressed, which may bring safety doubts in indoor air purification due to possible formation of harmful compounds. Here we show that in photocatalytic oxidation of formaldehyde–toluene and formaldehyde–xylene mixtures, the introduction of Pd cocatalyst on TiO2 photocatalyst successfully inhibits the formation of toxic methylphenols, thus promoting the complete mineralization of VOC mixtures into CO2 via the harmless benzaldehyde intermediates. Mechanistic analysis reveals that the loading of Pd cocatalyst effectively removes the inherent surface −OH groups of TiO2, which significantly promotes the activation of O2 into radical dotOH radicals. The Pd cocatalyst also directs the radical dotOH radicals to attack the methyl group instead of the aromatic ring for the formation of benzaldehyde and its further oxidation to CO2, thus yielding a better overall photocatalytic performance.
Indexed by:Journal paper
Volume:291
Page Number:120118
Translation or Not:no
Date of Publication:2021-03-10
Included Journals:SCI