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Titanium-decorated carbon nanotubes: a potential high-capacity hydrogen storage medium

T. Yildirim·S. Ciraci
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Abstract

We report a first-principles study, which demonstrates that a single Ti atom coated on a single-walled nanotube (SWNT) binds up to four hydrogen molecules. The first H$_2$ adsorption is dissociative with no energy barrier while other three adsorptions are molecular with significantly elongated H-H bonds. At high Ti coverage we show that a SWNT can strongly adsorb up to 8-wt% hydrogen. The system is quite stable and exhibits associative desorption upon heating, a requirement for reversible storage. These results advance our fundamental understanding of dissociative adsorption of hydrogen in nanostructures and suggest new routes to better storage and catalyst materials.

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T. Yildirim, S. Ciraci. 2005-04-26. Titanium-decorated carbon nanotubes: a potential high-capacity hydrogen storage medium. https://doi.org/10.1103/physrevlett.94.175501

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