Reversibility and Improved Hydrogen Release of Magnesium Borohydride
Abstract
Desorption and subsequent rehydrogenation of Mg(BH_4)_2 with and without 5 mol % TiF_3 and ScCl_3 have been investigated. Temperature programmed desorption (TPD) experiments revealed a significant increase in the rate of desorption as well as the weight percentage of hydrogen released with additives upon heating to 300 °C. Stable Mg(B_xH_y)_n intermediates were formed at 300 °C, whereas MgB_2 was the major product when heated to 600 °C. These samples were then rehydrogenated and subsequently characterized with powder X-ray diffraction (pXRD), Raman, and NMR spectroscopy. We confirmed significant conversion of MgB_2 to fully hydrogenated Mg(BH_4)_2 for the sample with and without additives. TPD and NMR studies revealed that the additives have a significant effect on the reaction pathway during both dehydrogenation and rehydrogenation reactions. This work suggests that the use of additives may provide a valid pathway for improving intrinsic hydrogen storage properties of magnesium borohydride.
Additional Information
© 2010 American Chemical Society. Received: December 9, 2009; Revised Manuscript Received: February 4, 2010. Publication Date (Web): February 25, 2010. The authors would like to thank George Sartor, Ken Stewart, and Jeff Chames for their skillful technical assistance. Assistance in sample handling by Joseph Reiter at JPL and David Abrecht at Caltech are greatly appreciated. We would also like to thank Craig Jensen, Ewa Ronnebro, Joe Cordaro, and Mitch Anstey for helpful discussions. We gratefully acknowledge financial support from the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, in the Hydrogen, Fuel Cells & Infrastructure Technologies Program under Contract Nos. DE-AC04-94AL85000, DE-AI- 01-05EE11104, and 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. JZZ is grateful to support by the Basic Energy Sciences (BES) Division of the US Department of Energy (DOE) (DE-FG02-06ER46251).Attached Files
Supplemental Material - jp9116744_si_001.pdf
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Additional details
- Eprint ID
- 17869
- DOI
- 10.1021/jp9116744
- Resolver ID
- CaltechAUTHORS:20100406-110448810
- DE-AC04-94AL85000
- Department of Energy (DOE)
- DE-AI- 01-05EE11104
- Department of Energy (DOE)
- DE-AI-01-05EE11105
- Department of Energy (DOE)
- DMR-9724240
- NSF
- DMR-0520565. JZZ
- NSF
- DE-FG02-06ER46251
- Department of Energy (DOE)
- Created
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2010-04-21Created from EPrint's datestamp field
- Updated
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2021-11-08Created from EPrint's last_modified field