Premium
Effects of Crystallization Atmospheres on the Near‐Infrared Absorbtion and Electroconductive Properties of Tungsten Bronze Type M x W O 3 ( M = Na , K )
Author(s) -
Guo Chongshen,
Yin Shu,
Sato Tsugio
Publication year - 2012
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2011.05039.x
Subject(s) - crystallization , calcination , materials science , tetragonal crystal system , amorphous solid , infrared , tungsten , electrical resistivity and conductivity , absorption (acoustics) , analytical chemistry (journal) , infrared spectroscopy , mineralogy , chemical engineering , chemistry , crystallography , crystal structure , optics , metallurgy , composite material , biochemistry , physics , electrical engineering , organic chemistry , chromatography , engineering , catalysis
The fine particles of tetragonal K x WO 3 and cubic Na x WO 3 were successfully synthesized by reducing WO 4 2− with BH 4 − in aqueous solutions, followed by the crystallization of amorphous precursors by calcination under N 2 , NH 3 and H 2 (5 vol%)/ N 2 atmospheres at 600°C for 1 h, respectively. The products showed excellent electrical conductivity, visible light transparency, and near‐infrared light shielding characteristics, where the samples crystallized in H 2 (5 vol%)/ N 2 mixed gas showed the highest electric conductivity being superior to commercial conductive oxide ITO . Meanwhile, the samples showed strong absorption of near‐infrared light and instantaneous conversion of photo‐energy to local heat. The effects of crystallization atmosphere on the near‐infrared absorbtion and electroconductivity properties of K x WO 3 and Na x WO 3 are discussed in detail.