Effects of TiO2 and Nb2O5 on Hydrogen Desorption of Mg(BH4)2

Authors: Wipada Ploysuksai, Pramoch Rangsunvigit, Santi Kulprathipanja

Abstract:

In this work, effects of catalysts (TiO2, and Nb2O5) were investigated on the hydrogen desorption of Mg(BH4)2. LiBH4 and MgCl2 with 2:1 molar ratio were mixed by using ball milling to prepare Mg(BH4)2. The desorption behaviors were measured by thermo-volumetric apparatus. The hydrogen desorption capacity of the mixed sample milled for 2 h was 4.78 wt% with a 2-step released. The first step occurred at 214 °C and the second step appeared at 374 °C. The addition of 16 wt% Nb2O5 decreased the desorption temperature in the second step about 66 °C and increased the hydrogen desorption capacity to 4.86 wt% hydrogen. The addition of TiO2 also improved the desorption temperature in the second step and the hydrogen desorption capacity. It decreased the desorption temperature about 71°C and showed a high amount of hydrogen, 5.27 wt%, released from the mixed sample. The hydrogen absorption after desorption of Mg(BH4)2 was also studied under 9.5 MPa and 350 °C for 12 h.

Keywords: hydrogen storage, LiBH4, metal hydride, Mg(BH4)2

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1079798

References:

[1] Ye, X., An, Y., and Xu, G. (2011). Kinetics of 9 - ethylcarbazole hydrogenation over Raney-Ni catalyst for hydrogen storage. Journal of Alloys and Compounds, 509, 152-156.
[2] Dong, J., Wang, X., Xu, H., Zhao, Q., and Li., J. (2007). Hydrogen storage in several microporous zeolites. International Journal of Hydrogen Energy, 32, 4998-5004.
[3] Hu, X., Fan, M., Towler,B.F., Radosz M., and Bell, D. A. (2011). Chapter 8 Hydrogen Adsorption and Storage. Coal Gasification and Its Applications., 188.
[4] Sakintuna, B., Darkrimb, F. L., Hirscherc, M. (2007). Metal hydride materials for solid hydrogen storage: A review. International Journal of Hydrogen Energy, 32, 1121-1140.
[5] Pistidda, C., Garroni, S., Dolci, F., Bardaj├¡, E. G., Khandelwal, A., Nolis, P., Dornheim, M., Gosalawit, R., Jensen, T., Cerenius, Y., Suriñach, S., Baro, M. D., Lohstroh, W., and Fichtner, M. (2010). Synthesis of amorphous Mg(BH4)2 from MgB2 and H2 at room temperature. Journal of Alloys and Compounds, 508, 212-215.
[6] Zhang, Z.G., Zhang, S.F., Wang, H., Liu, J.W., and Zhu, M. (2010). Feasibility study of the direct synthesis of Mg(BH4)2 complex hydrides by mechanical milling. International Journal of Hydrogen Energy, 505, 717-721.
[7] Matsunaga, T., Buchter, F., Miwa, K., Towata, S., Orimod, S., and Züttel, A. (2008). Magnesium borohydride: A new hydrogen storage. Renewable Energy, 33, 193-196.
[8] Matsunaga, T., Buchter, F., Mauron, P., Bielman, M., Nakamori, Y., Orimoc, S., Ohba, N., Miwa, K., Towata, S., and Züttel, A. (2008). Hydrogen storage properties of Mg(BH4)2. Journal of Alloys and Compounds, 459, 583-588.
[9] Li, H.-W., Kikuchi, K., Nakamori, Y., Miwa K, Towata, S., and Orimo, S. (2008). Effects of ball milling and additives on dehydriding behaviors of well-crystallized Mg(BH4)2. Scripta Materialia, 57, 679-682.
[10] Friedrichs, O., Klassen, T., Sánchez-López, J.C., Bormann, R., Fernández, A. (2006). Hydrogen sorption improvement of nanocrystalline MgH2 by Nb2O5 nanoparticles. Scripta Materialia, 54, 1293-1297.