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Updated: Sep 25, 2025
06:32
A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions
Published on: August 17, 2016
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A comprehensive study on lithium-based reactive hydride composite (Li-RHC) as a reversible solid-state hydrogen
Fahim Karimi1, Philipp Klaus Pranzas1, Julián Atillio Puszkiel1,2
1Department of Nanotechnology, Institute of Materials Research, Helmholtz-Zentrum HEREON Max-Planck-Straße 1 21502 Geesthacht Germany fahim.karimi2017hh@gmail.com.
RSC Advances
|April 28, 2022
Summary
Adding niobium pentafluoride (NbF5) significantly enhances the hydrogen storage kinetics of lithium borohydride-magnesium hydride (LiBH4-MgH2) composites. This breakthrough improves hydrogen release and uptake speeds by approximately 96% for sustainable energy applications.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Sustainable Energy Technologies
Background:
- Reversible solid-state hydrogen storage is crucial for clean energy solutions.
- The LiBH4-MgH2 composite offers high gravimetric capacity but suffers from slow kinetics.
- Sluggish dehydrogenation/hydrogenation rates (approx. 40 hours) limit practical applications.
Purpose of the Study:
- To significantly enhance the hydrogen storage kinetics of the LiBH4-MgH2 composite system.
- To investigate the catalytic mechanism of NbF5 in the dehydrogenation/hydrogenation process.
- To develop a model explaining NbF5's catalytic function.
Main Methods:
- Addition of a small amount of NbF5 to the LiBH4-MgH2 composite.
- Systematic investigation using advanced characterization techniques.
- In situ synchrotron radiation X-ray powder diffraction (SR-XPD), X-ray absorption spectroscopy (XAS), anomalous small angle X-ray scattering (ASAXS), and ultra/small-angle neutron scattering (USANS/SANS).
Main Results:
- Achieved a significant enhancement (approx. 96%) in the dehydrogenation/hydrogenation kinetics.
- Demonstrated the catalytic role of NbF5 in accelerating hydrogen release and uptake.
- Collected comprehensive data to support a mechanistic model.
Conclusions:
- NbF5 acts as an effective catalyst to overcome the kinetic limitations of LiBH4-MgH2.
- The study provides a pathway for developing practical solid-state hydrogen storage materials.
- Understanding the catalytic mechanism is key to optimizing hydrogen storage performance.
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