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A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
C60-mediated hydrogen desorption in Li-N-H systems
Zhao Qian1, Sa Li, Biswarup Pathak
1KTH Royal Institute of Technology, Department of Materials Science and Engineering, Applied Materials Physics, Stockholm, Sweden. zhaoq@kth.se
Nanotechnology
|November 10, 2012
Summary
Fullerenes like C(60) facilitate hydrogen desorption from lithium hydride (LiH) and ammonia mixtures. This process, crucial for fuel cells, becomes feasible at room temperature with C(60) stabilization.
Area of Science:
- Materials Science
- Chemical Engineering
- Computational Chemistry
Background:
- Hydrogen storage and release are critical for fuel cell technologies.
- Lithium hydride (LiH) and ammonia mixtures present challenges for hydrogen desorption due to stable LiNH(4) formation.
Purpose of the Study:
- To investigate the effect of C(60) fullerene on ammonia-mediated hydrogen desorption from LiH.
- To explore the potential of C(60) for enabling room-temperature hydrogen release.
Main Methods:
- First-principles calculations using cluster models.
- Molecular dynamic simulations.
Main Results:
- C(60) significantly stabilizes the intermediate LiNH(4) state, facilitating hydrogen desorption.
- The LiNH(4)-C(60) → LiNH(3)-C(60) + 1/2H(2) reaction pathway is exothermic.
- Hydrogen desorption is shown to occur at room temperature (300 K) in the presence of C(60).
Conclusions:
- C(60) enhances the thermodynamics of hydrogen desorption from LiH-NH(3) mixtures.
- This fullerene-mediated process allows for hydrogen release at practical temperatures.
- C(60) also mitigates the release of toxic ammonia gas, improving safety for fuel cell applications.
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