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Published on: August 17, 2016
Hydrogen-release mechanisms in lithium amidoboranes
Dong Young Kim1, N Jiten Singh, Han Myoung Lee
1Department of Chemistry, Pohang University of Science and Technology, Pohang, 790-784, Republic of Korea.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|April 17, 2009
Summary
Alkali-metal amidoboranes show promise for hydrogen storage. This study reveals lithium amidoboranes release H(2) via LiH formation and N-B bond catalysis, paving the way for improved hydrogen storage materials.
Area of Science:
- Materials Science
- Computational Chemistry
- Chemical Engineering
Background:
- Alkali-metal amidoboranes are promising candidates for hydrogen storage materials.
- Understanding their dehydrogenation mechanisms is crucial for developing effective hydrogen storage solutions.
Purpose of the Study:
- To elucidate the H(2) dehydrogenation mechanism in lithium amidoboranes.
- To investigate the role of Li cations in the dehydrogenation process.
Main Methods:
- High-level ab initio calculations were employed.
- Monomeric and dimeric lithium amidoborane compounds in the gas phase were studied.
Main Results:
- Hydrogen release involves LiH formation and a redox reaction of a dihydrogen bond.
- The Li cation catalyzes intermolecular N-B bond formation, potentially leading to N-B polymerization.
- A Li cation binding to nitrogen lowers the energy barrier for subsequent dehydrogenation.
Conclusions:
- The study provides insights into the H(2) release mechanism from lithium amidoboranes.
- Findings can guide the design of advanced hydrogen storage media.
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