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Updated: May 29, 2026
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
Potassium silanide (KSiH3): a reversible hydrogen storage material
Jean-Noël Chotard1, Wan Si Tang, Pascal Raybaud
1Laboratoire de Réactivité et Chimie des Solides, UMR 6007 CNRS Université de Picardie Jules Verne, 33 rue St Leu, 80039 Amiens, France.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|September 29, 2011
Summary
Potassium silicide (KSi) can absorb hydrogen, forming KSiH(3) for reversible hydrogen storage. This KSi/α-KSiH(3) system demonstrates a 4.3 wt% capacity within a favorable temperature and pressure range.
Area of Science:
- Materials Science
- Solid-state Chemistry
- Hydrogen Storage
Background:
- Developing efficient materials for reversible hydrogen storage is crucial for clean energy technologies.
- Metal hydrides offer potential for hydrogen storage, but often face challenges with thermodynamics and kinetics.
Purpose of the Study:
- To investigate the KSi/α-KSiH(3) system for its potential as a reversible hydrogen storage material.
- To determine the structural, thermodynamic, and hydrogen absorption properties of KSiH(3).
Main Methods:
- Neutron powder diffraction (NPD) was used to solve the crystal structure of α-KSiD(3).
- Density functional theory (DFT) calculations were employed to study thermodynamic and structural properties.
- Experimental measurements of hydrogen equilibrium pressures at various temperatures were conducted.
Main Results:
- The structure of α-KSiD(3) revealed unusually short Si-D bond lengths (1.47 Å).
- The KSi/α-KSiH(3) system exhibits a reversible hydrogen storage capacity of 4.3 wt%.
- A hydrogen equilibrium pressure of 0.1 MPa was achieved around 414 K, with a dehydrogenation enthalpy of ~23 kJ/mol H(2) and entropy of ~54 J/K mol H(2).
Conclusions:
- The KSi/α-KSiH(3) system shows promising characteristics for reversible hydrogen storage.
- Its high storage capacity and favorable thermodynamic properties make it a viable candidate for further research in this field.
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