ISSN:
1433-0768
Keywords:
Key words Tungsten trioxides
;
Tungsten trioxide hydrates
;
Hydrogen intercalation
;
X-ray powder diffraction
;
Infrared spectroscopy
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Hydrogen intercalation via spillover reaction in various tungsten trioxides leads to the formation of blue hydrogen bronzes. These reversible reactions induce changes in the W-O bond system while maintaining the W-O skeleton. The effect of the intercalation process on the host crystalline structure has been studied with respect to the ν(O-W-O) stretching vibration changes and lattice parameter variations by means of infrared and X-ray diffraction measurements. Among the main results, the intercalation process is shown to be strongly influenced by the structural type of the host compound as well as its amorphous versus crystalline nature. For instance, for the ReO3 type oxides (monoclinic and cubic WO3) and hexagonal WO3, ν(O-W-O) shifts to higher frequency are assigned to a shortening effect of W-O bonds. A W-O bond system arrangement is also measured for the crystallized and amorphous hydrates WO3 · H2O, but no detectable changes could be found in the pyrochlore WO3 and in the hydrate WO3·1/3 H2O.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s100080050049
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