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Updated: Sep 25, 2025
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
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.
Abstract:
Reversible solid-state hydrogen storage is one of the key technologies toward pollutant-free and sustainable energy conversion. The composite system LiBH4-MgH2 can reversibly store hydrogen with a gravimetric capacity of 13 wt%. However, its dehydrogenation/hydrogenation kinetics is extremely sluggish (∼40 h) which hinders its usage for commercial applications. In this work, the kinetics of this composite system is significantly enhanced (∼96%) by adding a small amount of NbF5. The catalytic effect of NbF5 on the dehydrogenation/hydrogenation process of LiBH4-MgH2 is systematically investigated using a broad range of experimental techniques such as in situ synchrotron radiation X-ray powder diffraction (in situ SR-XPD), X-ray absorption spectroscopy (XAS), anomalous small angle X-ray scattering (ASAXS), and ultra/small-angle neutron scattering (USANS/SANS). The obtained results are utilized to develop a model that explains the catalytic function of NbF5 in hydrogen release and uptake in the LiBH4-MgH2 composite system.
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