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Published on: August 17, 2016
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Hydrogen absorption and desorption in the V-Al-H system
Franziska Habermann1, Konrad Burkmann1, Bastian Hansel2
1TU Bergakademie Freiberg, Institut für Physikalische Chemie, Leipziger Str. 29, 09599 Freiberg, Germany. Florian.Mertens@chemie.tu-freiberg.de.
Dalton Transactions (Cambridge, England : 2003)
|March 21, 2023
Summary
Aluminium stabilizes vanadium hydride phases, enhancing hydrogen storage capacity and lowering pressures. However, the hypothetical V(AlH4) compound proved unstable under tested conditions.
Area of Science:
- Materials Science
- Hydrogen Storage
- Solid-State Chemistry
Background:
- Vanadium hydride (V-H) systems are crucial for hydrogen storage.
- Understanding alloying effects on V-H properties is key for material optimization.
Purpose of the Study:
- To investigate aluminium's influence on vanadium hydrogenation.
- To characterize the V-Al-H system and compare it to the V-H system.
- To explore the synthesis and stability of a hypothetical V(AlH4) compound.
Main Methods:
- Detailed study of the V-H system.
- Investigation of the V-Al-H system under varying conditions.
- Synthesis attempts via metathesis and direct hydrogenation.
Main Results:
- Aluminium exhibits a stabilizing effect on vanadium hydride phases.
- Aluminium acts as an oxygen getter, reducing equilibrium pressures.
- Increased hydrogen capacities were observed in the V-Al-H system compared to V-H.
- The hypothetical V(AlH4) compound was not successfully synthesized, indicating instability.
Conclusions:
- Aluminium addition beneficially modifies vanadium hydrogenation properties.
- The V-Al-H system shows promise for improved hydrogen storage applications.
- The instability of V(AlH4) suggests limitations for its use under ambient or moderate pressures and temperatures.
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