Supported titanium oxide species as photocatalysts in 2-propanol oxidation: Linking selectivity to structural and electronic properties

Moritz Lang, Marcus Klahn, Jennifer Strunk

Research output: Contribution to journalArticlepeer-review

Abstract

The photocatalytic performance of titanium oxide species supported on mesoporous silica (SBA-15) in the selective oxidation of 2-propanol is studied systematically as function of the titania surface loading. Monomers and oligomers of the supported titanium oxide species are formed on the silica surface in differing amounts with increasing loading, and the photocatalytic activity shows a strong dependence on the titanium content. A general advantage of supported samples in terms of net productivity could not be observed, but the photocatalysts’ longevity and selectivity improve with lower degrees of oligomerization. In-situ infrared spectroscopy in diffuse reflectance under irradiation revealed a likely explanation for this observation: The relative probability of the overoxidation of 2-propanol to acetate and possibly even total oxidation to CO2 increases with loading and is most severe for crystalline bulk titania. Stably adsorbed acetate appears to block the active sites on crystalline TiO2, but it is tolerable to a certain extent for the silica-supported samples. This work provides fundamental knowledge for the development of more stable and selective oxidation photocatalysts.

Original languageEnglish
Article number155623
JournalApplied Surface Science
Volume611
DOIs
StatePublished - 15 Feb 2023
Externally publishedYes

Keywords

  • DRIFTS
  • Heterogeneous photocatalysis
  • Selective oxidation
  • Single-site catalysts
  • TiO

Fingerprint

Dive into the research topics of 'Supported titanium oxide species as photocatalysts in 2-propanol oxidation: Linking selectivity to structural and electronic properties'. Together they form a unique fingerprint.

Cite this