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Remarkable hydrogen storage properties of MgH2 doped with VNbO5 Valentoni, Antonio Mulas, Gabriele Enzo, Stefano Garroni, Sebastiano Química física Chemistry, Physical and theoretical The present work concerns the catalytic effect of VNbO5, a ternary oxide prepared via a solid-state route, on the sorption performance of MgH2. Three doped systems, namely 5, 10 and 15 wt% VNbO5– MgH2 have been prepared by ball milling and thoroughly characterized. Hydrogen sorption, evaluated by temperature programmed desorption experiments, revealed a significant reduction of the desorption temperature from 330 1C for the un-doped sample (prepared and tested for comparison) to 235 1C for the VNbO5-doped sample. Furthermore, more than 5 wt% of hydrogen can be absorbed in 5 minutes at 160 1C under 20 bar of hydrogen, which is remarkable compared to the 0.7 wt% achieved for the un-doped system. The sample doped with 15 wt% of additive, showed good reversibility: over 5 wt% of hydrogen with negligible degradation even after 70 consecutive cycles at 275 1C and 50 cycles at 300 1C. The kinetics analysis carried out by Kissinger’s method exhibited a considerable reduction of the activation energy for the desorption process. Finally, pressure-composition-isotherm experiments conducted at three different temperatures allowed estimating the thermodynamic stability of the system and shed light on the additive role of VNbO5. 2021-05-24T09:40:47Z 2021-05-24T09:40:47Z 2018-02 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion 1463-9076 http://hdl.handle.net/10259/5779 10.1039/c7cp07157d 1463-9084 eng Physical Chemistry Chemical Physics. 2018, V. 20, n. 6, p. 4100-4108 https://doi.org/10.1039/C7CP07157D info:eu-repo/semantics/openAccess application/pdf Royal Society of Chemistry https://riubu.ubu.es/bitstream/10259/5779/3/Valentoni-pccp_2018.pdf.jpg Hispana TEXT http://rightsstatements.org/vocab/CNE/1.0/ RIUBU. Repositorio Institucional de la Universidad de Burgos http://hdl.handle.net/10259/5779