Influence of crystal structure on the chemical bonding nature and photocatalytic activity of hexagonal and cubic perovskite compounds

Hee Lee Sun, Young Kim In, Woo Kim Tae, Seong Ju Hwang

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

We have investigated the influence of the crystal structure on the chemical bonding nature and photocatalytic activity of cubic and hexagonal perovskite A[Cr1/2Ta1/2]O3 (A = Sr, Ba) compounds. According to neutron diffraction and field emission-scanning electron microscopy, the crystal structure and particle size of these compounds are strongly dependent on the nature of A-site cations. Also, it was found that the face-shared octahedra in the hexagonal phase are exclusively occupied by chromium ions, suggesting the presence of metallic (Cr-Cr) bonds. X-ray absorption and diffuse UV-vis spectroscopic analyses clearly demonstrated that, in comparison with cubic Sr[Cr1/2Ta1/2]O3 phase, hexagonal Ba[Cr1/2Ta1/2]O3 phase shows a decrease of Cr oxidation state as well as remarkable changes in interband Cr d-d transitions, which can be interpreted as a result of metallic (Cr-Cr) interactions. According to the test of photocatalytic activity, the present semiconducting materials have a distinct activity against the photodegradation of 4-chlorophenol. Also the Sr-based compound was found to show a higher photocatalytic activity than the Ba-based one, which is attributable to its smaller particle size and its stronger absorption in visible light region.

Original languageEnglish
Pages (from-to)817-821
Number of pages5
JournalBulletin of the Korean Chemical Society
Volume29
Issue number4
DOIs
Publication statusPublished - 2008 Apr 20

All Science Journal Classification (ASJC) codes

  • Chemistry(all)

Fingerprint Dive into the research topics of 'Influence of crystal structure on the chemical bonding nature and photocatalytic activity of hexagonal and cubic perovskite compounds'. Together they form a unique fingerprint.

  • Cite this