In:
Journal of Materials Research, Springer Science and Business Media LLC, Vol. 16, No. 8 ( 2001-08), p. 2256-2263
Abstract:
A series of photochromic sol-gel films are prepared through entrapping tungsten heteropolyoxometallates (PW 12 O 40 3− , SiW 12 O 40 4− ) and molybdenum heteropolyoxometallate (PMo 12 O 40 3− ) into a kind of inorganic–organic matrix cohydrolyzed from tetraethylorthosilicate and 3-aminopropyltriethoxysilane. The films show reversible photochromicity. Irradiated with ultraviolet light, the transparent films change from colorless to blue. Then, bleaching occurs when the films are in contact with air or O 2 in the dark. The Keggin-type polyanions interact with R–NH 3 + cations strongly, and thus disperse uniformly in the sol-gel matrix, as proved by Fourier transform infrared spectra and x-ray diffraction. The molybdenum heteropolyoxometallate sol-gel film has higher photochromic efficiency and much slower bleaching than its counterparts of tungsten heteropolyoxometallate. A charge-transfer model which is supported by electron spin resonance and related literature [T. Yamase, Chem. Rev. 98, 307, (1998)] is put forth to explain the above experimental results.
Type of Medium:
Online Resource
ISSN:
0884-2914
,
2044-5326
DOI:
10.1557/JMR.2001.0310
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2001
detail.hit.zdb_id:
54876-5
detail.hit.zdb_id:
2015297-8
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