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Lewis base assisted B-H bond redistribution in borazine and polyborazylene
Benjamin L Davis1, Brian D Rekken, Ryszard Michalczyk
1MS-J514, MPA-MSID, Materials Synthesis and Integrated Devices, Los Alamos National Laboratory, Los Alamos, NM 87545, USA. bldavis@lanl.gov.
Chemical Communications (Cambridge, England)
|August 22, 2013
Summary
Lewis bases react with borazine and polyborazylene to form ammonia-borane (AB) adducts. This reaction offers a potential pathway for recovering AB and enhancing regeneration methods.
Area of Science:
- Inorganic Chemistry
- Materials Science
Background:
- Borazine and polyborazylene are nitrogen-boron compounds with potential applications in hydrogen storage.
- Ammonia-borane (AB) is a promising material for hydrogen storage but faces challenges in regeneration.
Purpose of the Study:
- To investigate the reaction of Lewis bases with borazine and polyborazylene.
- To explore a novel method for ammonia-borane (AB) recovery and regeneration.
Main Methods:
- Reaction of ammonia (NH3) with borazine and polyborazylene.
- Quantification of ammonia-borane (AB) using Nuclear Magnetic Resonance (NMR) spectroscopy with an internal standard.
- Computational calculations to determine reaction driving forces.
Main Results:
- Ammonia-borane (AB) adducts were successfully formed and quantified.
- Calculations suggest the formation of B(NH2)3 as a driving force for the observed redistribution.
- A new chemical pathway for AB recovery was identified.
Conclusions:
- The reaction of Lewis bases with borazine/polyborazylene provides a viable route for ammonia-borane (AB) recovery.
- This chemistry could simplify and reduce the cost of spent AB regeneration.
- Further research into this redistribution chemistry is warranted to optimize AB regeneration processes.
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