Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published January 2009 | public
Journal Article

Magnesium borohydride as a hydrogen storage material: Properties and dehydrogenation pathway of unsolvated Mg(BH_4)_2

Abstract

The decomposition of crystalline magnesium borohydride upon heating was studied using thermal desorption, calorimetry, in situ X-ray diffraction, and solid state NMR. Hydrogen release from Mg(BH_4)_2 occurs in at least four steps via formation of several polyborane intermediate species and includes an exothermic reaction yielding crystalline MgH_2 as an intermediate. The decomposition products may be only partially recharged after the very first step and also via hydrogenation of Mg metal. The intermediate formation of amorphous MgB_(12)H_(12), was confirmed by ^(11)B NMR. A four-stage pathway for the thermal decomposition of Mg(BH_4)_2 is proposed.

Additional Information

© 2008 International Association for Hydrogen Energy. Received 27 May 2008; revised 9 July 2008; accepted 5 November 2008. Available online 13 December 2008. The authors acknowledge valuable technical assistance from Tom Raber and Maria LaTorre at GE Global Research and Dr. Jonathan Hanson at Brookhaven National Laboratory. SJH and RCB thank Dr. S. S. Jalisatgis of U. Missouri Columbia for providing the K_2B_(12)H_(12) and K_2B_(10)_H(10) reference materials. Use of the National Synchrotron Light Source, Brookhaven National Laboratory, was supported by the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-98CH10886. Part of the work was supported by DOE, Office of Energy Efficiency and Renewable Energy, under Contract No. DE-FC3605GO15062 as part of the DOE Metal Hydride Center of Excellence. This research was partially performed at the Jet Propulsion Laboratory, which is operated by the California Institute of Technology under contract with the NASA. This work was partially supported by DOE through Award Number DE-AI-01- 05EE11105. The NMR facility at Caltech was supported by the National Science Foundation (NSF) under Grant Number 9724240 and partially supported by the MRSEC Program of the NSF under Award Number DMR-0520565.

Additional details

Created:
August 22, 2023
Modified:
October 18, 2023