High-Pressure Polymorph of NaBiO3

Octavianti Naa; Nobuhiro Kumada; Akira Miura; Takahiro Takei; Masaki Azuma; Yoshihiro Kusano; Kengo Oka

doi:10.1021/acs.inorgchem.6b00947

High-Pressure Polymorph of NaBiO3

Inorg Chem. 2016 Jun 20;55(12):5747-9. doi: 10.1021/acs.inorgchem.6b00947. Epub 2016 May 31.

Authors

Octavianti Naa¹, Nobuhiro Kumada¹, Akira Miura², Takahiro Takei¹, Masaki Azuma³, Yoshihiro Kusano⁴, Kengo Oka⁵

Affiliations

¹ Center for Crystal Science and Technology, University of Yamanashi , 7-32 Miyamae-cho, Kofu 400-8511, Japan.
² Faculty of Engineering, Hokkaido University , Kita 13, Nishi 8, Kita-ku, Sapporo 060-8628, Japan.
³ Materials and Structural Laboratory, Tokyo Institute of Technology 4259 Nagatsuta, Midori-ku Yokohama, Kanagawa 226-8503, Japan.
⁴ Department of Applied Arts and Design, Kurashiki University of Science and the Arts , 2640 Nishinoura, Tsurajima-cho, Kurashiki, Okayama 712-8505, Japan.
⁵ Faculty of Science and Engineering, Chuo University , 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.

PMID: 27243818
DOI: 10.1021/acs.inorgchem.6b00947

Abstract

A new high-pressure polymorph of NaBiO3 (hereafter β-NaBiO3) was synthesized under the conditions of 6 GPa and 600 °C. The powder X-ray diffraction pattern of this new phase was indexed with a hexagonal cell of a = 9.968(1) Å and c = 3.2933(4) Å. Crystal structure refinement using synchrotron powder X-ray diffraction data led to RWP = 8.53% and RP = 5.55%, and the crystal structure was closely related with that of Ba2SrY6O12. No photocatalytic activity for phenol decomposition was observed under visible-light irradiation in spite of a good performance for its mother compound, NaBiO3. The optical band-gap energy of β-NaBiO3 was narrower than that of NaBiO3, which was confirmed with density of states curves simulated by first-principles density functional theory calculation.