Roles of the active species involved in the photocatalytic oxidation of benzyl alcohol into benzaldehyde on TiO2 under UV light : Experimental and DFT studies

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

29 Scopus Citations
View graph of relations

Author(s)

Detail(s)

Original languageEnglish
Pages (from-to)82-87
Journal / PublicationJournal of Molecular Catalysis A: Chemical
Volume420
Publication statusPublished - 1 Aug 2016

Abstract

Active species such as holes, electrons, hydroxyl radicals (•OH), and superoxide radical anions (O2 •-) involved in the photocatalytic oxidation of benzyl alcohol (BA) into benzaldehyde (BAD) on TiO2 under ultraviolet (UV) light were investigated by adding corresponding scavengers. The experimental results show that the oxidation of BA into BAD is driven mainly by the holes and •OH radical. The role of dissolved O2 was studied by bubbling N2 through the reaction. The results show that the dissolved O2 is, to some extent, the source of •OH. Additional density functional theory (DFT) calculations identified two H-abstraction pathways (RabsOH and Rabsα). The structure of the RabsOH product is less stable and tends to transfer resulting in the Rabs α product. The holes are the main driving force for the abstracting of H from BA. The •OH radical combines with the H-abstract product to form a precursor of product BAD, detected by LC-MS technique (m/z 123), which then undergoes an intramolecular dehydration reaction to form BAD. The results will help to select the optimal active species for the photocatalytic oxidation of BA into BAD on TiO2 under UV light.

Research Area(s)

  • Active species, Benzyl alcohol, DFT calculation, Photocatalytic oxidation, Reaction mechanism

Citation Format(s)

Roles of the active species involved in the photocatalytic oxidation of benzyl alcohol into benzaldehyde on TiO2 under UV light: Experimental and DFT studies. / Zhao, Lei; Zhang, Baoyue; Xiao, Xin et al.
In: Journal of Molecular Catalysis A: Chemical, Vol. 420, 01.08.2016, p. 82-87.

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review