The Effects of Oxidized and Oxide-Free Boron on the Mg-B-H Nanohydrides Transformation in the Nearly Nanosized Powders

Article Preview

Abstract:

In this work oxidized and oxide-free amorphous boron (a-B) powder and elemental Mg were used in an attempt to directly synthesize the Mg(BH4)2 complex hydride by controlled reactive mechanical alloying (CRMA) under hydrogen in a magneto-mill up to 200h. The particle size was refined to the 100-200nm range. Nanocrystalline MgH2 (~6nm crystallite size) was formed within the particles when an oxidized a-B is used. In contrast, a mixture of MgB2 and an amorphous hydride MgHx was formed when an oxide-free a-B was used. Differential scanning calorimetry (DSC) test up to 500°C produced a single endothermic heat event at 357.7°C due to hydrogen desorption. In addition, desorption conducted in a Sieverts-type apparatus revealed ~1.4wt.% of hydrogen release. The X-ray diffraction pattern after DSC test of the 200h milled sample made with oxide-free boron showed the presence of MgB2.

You might also be interested in these eBooks

Info:

Periodical:

Solid State Phenomena (Volume 128)

Pages:

47-52

Citation:

Online since:

October 2007

Export:

Price:

Permissions CCC:

Permissions PLS:

Сopyright:

© 2007 Trans Tech Publications Ltd. All Rights Reserved

Share:

Citation:

[1] J.A. Ritter, A.D. Ebner, J. Wang and R. Zidan: Materials Today Vol. 6 (9)(2003), pp.18-23.

Google Scholar

[2] A. Züttel, P. Wenger, S. Rentsch, P. Sudan, Ph. Mauron and Ch. Emmenegger: J. Power Sourc. Vol. 118 (2003), pp.1-7.

DOI: 10.1016/s0378-7753(03)00054-5

Google Scholar

[3] L. Schlapbach and A. Züttel: Nature Vol. 414 (2001), pp.353-358.

Google Scholar

[4] D.S. Stasinevich and G.A. Egorenko: Russian J. Inorg. Chem. Vol. 13 (1968), pp.341-343.

Google Scholar

[5] V.N. Konoplev and V.M. Bakulina: Izv. Akad. Nauk SSSR Vol. 1 (1971), pp.159-161.

Google Scholar

[6] M. Fichtner: Adv. Eng. Mater. Vol. 7 (2005), pp.443-455.

Google Scholar

[7] R.A. Varin and T. Czujko: Mater. Manuf. Proc. Vol. 17 (2002), pp.129-156.

Google Scholar

[8] J. Huot, G. Liang and R. Schulz: Appl. Phys. A Vol. 72 (2001), pp.187-195.

Google Scholar

[9] A. Zaluska, L. Zaluski and J.O. Ström-Olsen: Appl. Phys. A Vol. 72 (2001), pp.157-165.

Google Scholar

[10] A. Zaluska, L. Zaluski, and J.O. Ström-Olsen: J. Alloys&Comp. Vol. 288 (1999), pp.217-225.

Google Scholar

[11] M. Fichtner and O. Fuhr: J. Alloys&Comp. Vol. 345 (2002), pp.286-296.

Google Scholar

[12] M. Fichtner, O. Fuhr and O. Kircher: J. Alloys&Comp. Vol. 356-357 (2003), pp.418-422.

Google Scholar

[13] M. Schwarz, A. Haiduc, H. Stil, P. Paulus and H. Geerlings: J. Alloys&Comp. Vol. 404-406 (2005), pp.762-765.

Google Scholar

[14] A. Calka and A.P. Radlinski: Mater. Sci. Eng. A Vol. 134 (1991), pp.1350-1353.

Google Scholar

[15] Patents: WO9104810, US5383615, CA2066740, EP0494899, AU643949.

Google Scholar

[16] A. Calka and R.A. Varin, in: Proceeding of the International Symposium on Processing and Fabrication of Advanced Materials IX PFAM-IX, edited by T.S. Srivatsan, R.A. Varin, M. Khor ASM International, Materials Park, OH (2001), pp.263-287.

DOI: 10.1002/maco.200390064

Google Scholar

[17] R.A. Varin, T. Czujko and Z. Wronski: Nanotechnology Vol. 17 (2006), pp.3856-3865.

Google Scholar

[18] M.W. Chase, Jr: J. Phys. &Chem. Ref. Data-Monograph No. 9; NIST-JANAF Thermochemical Tables, 4th Ed. (1998), p.268.

Google Scholar

[19] B. Bogdanović, A. Reiser, K. Schlichte, B. Spliethoff and B. Tesche: J. Alloys&Comp. Vol. 345 (2002) pp.77-89.

Google Scholar