SYNTHESIS AND HYDROGEN DESORPTION PROPERTIES
2803
(A = 1.2 × 1010 and Ea = 102.2 3.2 kJ/mol) consid-
erably. It is worthwhile mentioning that the particle
diameter of as-prepared α-AlH3 is around 60 nm,
while that of α-AlH3 prepared by Herley et al. and
Graetz et al. are 100 μm and 204 nm, respectively.
Thus, it can be concluded that the significantly
decreasing of the pre-exponential factor and activa-
tion energy for α-AlH3 is attributed to the smaller par-
ticle size. As the grain size of α-AlH3 decreases, the
specific surface area become larger so that its molar
surface energy increases. That improves the average
molar energy of the α-AlH3, thereby reducing the gap
(activation energy) between the average energy of
1 mol activated molecules and 1 mol reactants.
4. H. Liu, X. Wang, Z. Dong, G. Cao, Y. Liu, L. Chen,
and M. Yan, Int. J. Hydrogen Energy 38, 10851 (2013).
5. F. M. Brower, N. E. Matzek, P. F. Reigler, H. W. Rinn,
C. B. Roberts, D. L. Schmidt, J. A. Snover, and
K. Terada, J. Am. Chem. Soc. 98, 2450 (1976).
6. T. Roubicek and G. Tomassetti, Discrete Cont. Dyn.
Syst., Ser. B 19, 2313 (2017).
7. H. Liu, X. Wang, H. Zhou, S. Gao, H. Ge, S. Li, and
M. Yan, Int. J. Hydrogen Energy 41, 22118 (2016).
8. R. Chen, C. L. Duan, X. Liu, K. Qu, G. Tang, X. X. Xu,
and B. Shan, J. Vacuum Sci. Technol. A 35, 03E111
(2017).
9. J. Graetz, Chem. Soc. Rev. 38, 73 (2009).
10. S. Gao, H. Liu, X. Wang, L. Xu, S. Liu, P. Sheng,
G. Zhao, B. Wang, H. Li, and M. Yan, Int. J. Hydrogen
Energy 42, 25310 (2017).
CONCLUSION
11. J. Graetz and J. J. Reilly, J. Phys. Chem. B 109, 22181
(2005).
Single-phase nanoscale α-AlH3 was synthesized by
modified ethereal reaction method. According to
Avrami–Erofeyev equation, the decomposition kinet-
ics of nanoscale α-AlH3 are controlled by nucleation
and growth of the aluminum phase in three rather than
two dimensions, different from micro and sub-micro
α-AlH3. The activation energy and pre-exponential
factor of dehydriding of as-prepared nanoscale
α-AlH3 was estimated to be 93.23 kJ/mol and 7.49 ×
12. R. Zidan, B. L. Garcia- Diaz, C. S. Fewox, A. C. Stowe,
J. R. Gray, and A. G. Harter, Chem. Commun., 3717
(2009).
13. S. Kato, M. Bielmann, K. Ikeda, S. Orimo, A. Borg-
schulte, and A. Züttel, Appl. Phys. Lett. 96, 687 (2010).
14. J. Graetz and J. J. Reilly, J. Alloys Compd. 424, 262
(2006).
15. Y. Nakagawa, S. Isobe, Y. Wang, N. Hashimoto,
S. Ohnuki, L. Zeng, S. Liu, T. Ichikawa, and Y. Koji-
ma, J. Alloys Compd. 580, S163 (2013).
108, respectively. The activation energy is significantly
lower than that for the micron and sub-micron size
α-AlH3. The activation energy of nanoscale α-AlH3
decomposition is significantly reduced as a result of
smaller grain diameter. Thus, the synthesis of α-AlH3
with smaller particle size may be an effective way to
solve the difficulties in application of AlH3.
16. P. J. Herley and O. Christofferson, J. Phys. Chem. 85,
1874 (1981).
17. T. T. Ma and R. X. Gu, Power Technol. 31, 95 (2014).
18. I. Gabis, M. Dobrotvorskiy, E. Evard, and A. Voyt,
J. Alloys Compd. 509, S671 (2011).
19. J. Graetz and J. J. Reilly, J. Phys. Chem. B 109, 22181
(2005).
ACKNOWLEDGMENTS
20. W. Jeong, S. H. Lee, and J. Kim, J. Nanosci. Nano-
technol. 16, 2987 (2016).
This work was supported by the National Key R&D
Program of China (grant no. 2017YFB1300104), National
Natural Science Foundation of China (grant no. 21571042,
21371040), Science Foundation of Aerospace (grant
nos. 6141B0626020201, 6141B0626020101) and the Post-
doctoral Foundation of Heilongjiang Province (grant
no. LBH-Z16059).
21. J. G. And and J. J. Reilly, J. Phys. Chem. B 109, 22181
(2005).
22. T. B. Tang and M. M. Chaudhri, J. Therm. Anal. 18,
247 (1980).
23. H. Borchert, E. V. Shevchenko, A. Robert, I. Mekis,
A. Kornowski, G. Grübel, and H. Weller, Langmuir
21, 1931 (2005).
24. Y. Wang, J. A. Yan, and M. Y. Chou, Phys. Rev. B 77
REFERENCES
(1) (2008).
25. J. H. Sharp, G. W. Brindley, and B. N. N. Achar,
1. C. W. Duan, L. X. Hu, and J. L. Ma, J. Mater. Chem.
J. Am. Ceram. Soc. 49, 379 (1966).
A 6, 6309 (2018).
26. M. Zhou, Q. L. Xu, P. Lan, W. Yuan, X. Y. Sun,
S. Z. Xin, and Y. J. Yan, J. Jilin Inst. Chem. Technol.
26, 35 (2009).
2. H. Liu, X. Wang, Y. Liu, Z. Dong, S. Li, H. Ge, and
M. Yan, J. Phys. Chem. C 118, 18908 (2014).
3. H. Liu, X. Wang, Y. Liu, Z. Dong, H. Ge, S. Li, and
27. C. P. Constantinou, Int. J. Chem. Kinet. 26, 1151
M. Yan, J. Phys. Chem. C 118, 37 (2013).
(1994).
RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A Vol. 93 No. 13 2019