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Updated: Jun 6, 2026

Supercritical Nitrogen Processing for the Purification of Reactive Porous Materials
Published on: May 15, 2015
Reversible dehydrogenation of magnesium borohydride to magnesium triborane in the solid state under moderate
Marina Chong1, Abhi Karkamkar, Tom Autrey
1Department of Chemistry, University of Hawaii at Manoa, 2545 McCarthy Mall, Honolulu, HI 96822-2275, USA.
Abstract:
Thermal decomposition of magnesium borohydride, Mg(BH(4))(2), in the solid state was studied by a combination of PCT, TGA/MS and NMR spectroscopy. Dehydrogenation of Mg(BH(4))(2) at 200 °C en vacuo results in the highly selective formation of magnesium triborane, Mg(B(3)H(8))(2). This process is reversible at 250 °C under 120 atm H(2). Dehydrogenation at higher temperature, >300 °C under a constant argon flow of 1 atm, produces a complex mixture of polyborane species. A borohydride condensation mechanism involving metal hydride formation is proposed.
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