The gasochromic mechanism in amorphous tungsten oxide films has been investigated using Raman scattering measurements. The Raman spectra of as-deposited films show two strong peaks at 770 and 950 cm−1 due to vibrations of the O–W6+O and W6+=O bonds, respectively. When the Pd/a-WO3 films are gasochromically colored by exposure to diluted hydrogen gas, extra Raman peaks due to O–W5+O and W5+=O bonds appear at 330 and 450 cm−1, respectively. The Raman spectra of a-WO3 films bleached with isotopic heavy oxygen (18O) show that the gasochromic coloration in a-WO3 films is directly related to the double injection of hydrogen ions and electrons.

1.
S. K.
Deb
,
Appl. Opt. Suppl.
3
,
192
(
1969
);
S. K.
Deb
,
Philos. Mag.
27
,
801
(
1973
).
2.
C. G. Granqvist, Handbook of Inorganic Electrochromic Materials (Elsevier, New York, 1995), p. 5.
3.
A.
Georg
,
W.
Graf
,
D.
Schweiger
,
V.
Wittwer
,
P.
Nitz
, and
H. R.
Wilson
,
Sol. Energy
62
,
215
(
1998
).
4.
J. Schoonman, Proceedings of the International Seminar Solid State Ionic Devices (World Scientific, Singapore, 1988), pp. 697–717.
5.
D. K. Benson, C. E. Tracy, G. A. Hishmeh, P. E. Ciszek, S.-H. Lee, and D. P. Haberman, Proc. SPIE 3535, 185.
6.
B. W.
Faughnan
,
R. S.
Crandall
, and
P. M.
Heyman
,
RCA Rev.
36
,
177
(
1975
).
7.
A.
Georg
,
W.
Graf
,
R.
Neumann
, and
V.
Wittwer
,
Solid State Ionics
127
,
319
(
2000
).
8.
Y.
Shigesato
,
A.
Murayama
,
T.
Kamimori
, and
K.
Matsuhiro
,
Appl. Surf. Sci.
33/34
,
804
(
1988
).
9.
J. V.
Gabrusenoks
,
P. D.
Chikmach
,
A. R.
Lusis
,
J. J.
Kleperis
, and
G. M.
Ramans
,
Solid State Ionics
14
,
25
(
1984
).
10.
S.-H.
Lee
,
H. M.
Cheong
,
J.-G.
Zhang
,
A.
Mascarenhas
,
D. K.
Benson
, and
S. K.
Deb
,
Appl. Phys. Lett.
74
,
242
(
1999
).
11.
S.-H.
Lee
,
H. M.
Cheong
,
J.-G.
Zhang
,
C. Edwin
Tracy
,
A.
Mascarenhas
,
D. K.
Benson
, and
S. K.
Deb
,
Electrochim. Acta
44
,
3111
(
1999
).
12.
S.-H.
Lee
,
H. M.
Cheong
,
C. E.
Tracy
,
A.
Mascarenhas
,
A. W.
Czanderna
, and
S. K.
Deb
,
Appl. Phys. Lett.
75
,
1541
(
1999
).
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