Effect of particle size on the photocatalytic activity of WO3 particles for water oxidation

Fumiaki Amano, Eri Ishinaga, Akira Yamakata

Research output: Contribution to journalArticlepeer-review

162 Citations (Scopus)


The particle size of a photocatalyst is one of the factors that determine the photon utilization efficiency. Here, we report the effects of the particle size on the photocatalytic activity of tungsten trioxide (WO3) for water oxidation to evolve molecular oxygen in the presence of sacrificial silver nitrate. For the water oxidation, the photocatalytic activity of large aggregates consisting of particles with a small specific surface area (3 m 2 g-1) was greater than that of fine particles with a larger specific surface area (11 m2 g-1). Transient infrared absorption spectra revealed that the recombination of photoexcited electrons in the large particles was slower than that in the fine particles. It was found that the fast recombination in the fine particles mostly occurred on the surface. The photocatalytic activity for water oxidation increased with increasing particle size for spherical diameters smaller than 200 nm. These results showed that large particles with a low surface area-to-volume ratio were suitable for photocatalytic oxygen evolution, which requires long-lived holes, because the surface recombination of photogenerated electrons and holes occurred less frequently.

Original languageEnglish
Pages (from-to)22584-22590
Number of pages7
JournalJournal of Physical Chemistry C
Issue number44
Publication statusPublished - Nov 7 2013
Externally publishedYes

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Energy(all)
  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films


Dive into the research topics of 'Effect of particle size on the photocatalytic activity of WO3 particles for water oxidation'. Together they form a unique fingerprint.

Cite this