Photolysis of HCOOH over Rh deposited on pure and N-modified TiO 2: Production of pure H 2

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

The photo-induced vapor-phase decomposition of formic acid was investigated on pure, N-doped and Rh-promoted TiO 2. The bandgap of TiO 2 was narrowed by 0.82-1.04 eV as a result of the incorporation N into TiO 2. Adsorption of formic acid on pure TiO 2 produced strong absorption bands due to formate species, the intensity of which decreased by illumination. The photodecomposition of formic acid on pure TiO 2 at 300 K occurs to only a limited extent: on N-doped TiO 2, however, it is enhanced by a factor of 2-4. The N-modified TiO 2 catalyzes the photoreaction even in the visible light, which is attributed to the prevention of electron-hole recombination. The deposition of Rh on TiO 2 markedly increased the extent of photodecomposition. The conversion is complete in 200 min, while the extent of decomposition reaches only ~30% on pure TiO 2. The effect of Rh is explained by a better separation of charge carriers induced by illumination and by enhanced electron donation to the adsorbed formate species. On TiO 2 samples both the dehydrogenation and dehydration reactions occurred, on Rh/TiO 2 only a trace amount of CO was formed. Addition of water to formic acid eliminated this CO, but exerted no other influence on the occurrence the photoreaction. Graphical Abstract: Effects of illumination time on the formation of CO 2 and CO on pure and N-doped TiO 2 in the photodecomposition of HCOOH.[Figure not available: see fulltext.]

Original languageEnglish
Pages (from-to)218-223
Number of pages6
JournalCatalysis Letters
Volume142
Issue number2
DOIs
Publication statusPublished - Feb 1 2012

Keywords

  • N-doped TiO
  • Photodecomposition of formic acid
  • Rh-promoted TiO
  • TiO photocatalyst

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)

Fingerprint Dive into the research topics of 'Photolysis of HCOOH over Rh deposited on pure and N-modified TiO <sub>2</sub>: Production of pure H <sub>2</sub>'. Together they form a unique fingerprint.

  • Cite this