1508
OL’SHANSKAYA et al.
0
1/2
Table 2. Constants of hydrogen sorption by LiLaAlox electrode from a 1.5% HCl solution and c D product at different
cathodic polarization potentials
3
c0D1/2 10 (ox),
8
Ki 103 (M),
c0 D1/2 108 (M),
mol cm 2 s 1/2
Ki 10 (ox),
E , V
cp
A s1/2 cm 2
mol cm 2
1/2
A s1/2 cm 2
s
2
2
1
1
.2
.0
.5
.1
1.2
1.4
1.3
1.0
2.2
2.6
2.4
1.8
0.25
0.44
0.38
0.42
0.5
0.8
0.7
0.8
lowing exchange reactions are possible:
LiAl + xH+ + xe = AlH Li
REFERENCES
+ xLi
1 x
1. Gamburg, D.Yu., Semenov, V.P., Dubovkin, N.F., and
Smirnova, L.N., Vodorod: Svoistva, poluchenie, khra-
nenie, transportirovanie, primenenie: Spravochnoe
izdanie (Hydrogen: Propeties, Manufacture, Storage,
Transportation, and Use: Reference Book), Moscow:
Khimiya, 1989.
x
or
La + xH+ + xe = LaH ,
x
Li + xH+ + xe = LiH .
x
2
. Marshakov, A.I. and Mikhailovskii, Yu.N., Elektro-
khimiya, 1994, vol. 30, no. 4, pp. 530 543.
It was established experimentally that hydrogen is
sorbed from HCl solutions at a higher rate. In the case
of HClO , adsorption of ClO anions on the alloy sur-
3. Grilikhes, M.S. and Bozhevol’nov, V.B., Zh. Prikl.
Khim., 1995, vol. 68, no. 3, pp. 353 365.
4
4
+
face hinders introduction of H ions into the structure
of the electrode, and an additional energy is required
for this process to begin. This is achieved, for exam-
ple, at a significant shift of the cathodic polarization
potential in the negative direction (to +0.05 V relative
4
. Korovin, N.V., Elektrokhimiya, 1971, vol. 8, no. 2,
pp. 172 179.
5
. Kuznetsov, V.V., Khaldeev, G.V., and Kichigin, V.I.,
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shinostroenie, 1993.
+
to Li /Li and 3.0 V relative to the nonaqueous silver
chloride electrode).
6
. Skuratnik, L.B., Elektrokhimiya, 1977, vol. 13, no. 8,
Raising the concentration of HCl from 0.375 to
pp. 1122 1126.
1
4
.5 wt % makes the rate of hydrogen intercalation 3
times faster. In this case, the electrochemical param-
7. Krapivnyi, N.G., Elektrokhimiya, 1981, vol. 17, no. 5,
pp. 634 637.
eters of the process depend on Ecp (Table 2).
CONCLUSIONS
1) In the chosen modes of preliminary thermal
treatment and oxidation, an oxide film whose proper-
ties and structure favor cathodic intercalation of La
and Li into an aluminum electrode is formed on the
Al surface.
8. Krapivnyi, N.G., Elektrokhimiya, 1981, vol. 17, no. 5,
pp. 678 685.
9
. Petrii, O.A. and Kolotyrkina, T.Ya., Elektrokhimiya,
973, vol. 9, no. 2, pp. 254 257.
1
(
1
0. Korkashvili, T.Sh., Tsionskii, V.M., and Krishta-
lik, L.I., Elektrokhimiya, 1980, vol. 16, no. 6, pp. 886
8
88.
1
1
1
1. Batrakov, V.V., Dittrich, J., and Popova, A.N., Elek-
trokhimiya, 1972, vol. 8, no. 4, pp. 640 643.
(2) Introduction of lithium and lanthanum is ac-
2. Kudryashov, I.V. and Falin, L.A., Elektrokhimiya,
companied by successive distortion of the crystal
lattice by La and Li and formation of additional
vacancies and structural defects and of zones with an
increased diffusion rate. This facilitates the sub-
sequent sorption of hydrogen and its accommodation
in the structure of the LiLaAl alloys formed.
1971, vol. 7, no. 12, pp. 1770 1772.
3. Lavrenko, V.A., Yagupol’skaya, L.N., and Ti-
kush, V.L., Elektrokhimiya, 1970, vol. 6, no. 6,
pp. 887 890.
1
4. Butler, J., Elektrokhimiya metallov v nevodnykh rast-
vorakh (Electrochemistry of Metals in Nonaqueous
Solutions), Moscow: Mir, 1974.
(3) Hydrogen sorption is affected by the solution
concentration and nature (anionic composition) of
a hydrogen-containing agent.
15. Vetter, K.J., Electrochemische Kinetik, Berlin:
Springer, 1961.
RUSSIAN JOURNAL OF APPLIED CHEMISTRY Vol. 77 No. 9 2004