2026-04-23T00:00:41Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/48342024-07-24T11:37:27Zcom_10259_9476com_10259.4_106com_10259_2604col_10259_9477

Kinetics and hydrogen storage performance of Li-Mg-N-H systems doped with Al and AlCl3 Senes, Nina . Fernández Albanesi, Luisa . Garroni, Sebastiano Santoru, Antonio . Pistidda, Claudio . Mulas, Gabriele Enzo, Stefano Gennari, Fabiana C. Hydrogen absorbing materials Mechanochemical processing Kinetics Diffusion Crystal structure Recent investigations showed the formation of new amide-chloride phases between LiNH2 and AlCl3 after milling and/or heating under hydrogen pressure. These phases exhibited a key role in the improvement of the hydrogen storage properties of the LiNH2-LiH composite. In the present work, we studied the effects of Al and AlCl3 additives on the hydrogen storage behavior of the Li-Mg-N-H system. The dehydrogenation kinetics and the reaction pathway of Al and AlCl3 modified LiNH2-MgH2 composite were investigated through a combination of kinetic measurements and structural analyses. During the first cycle, the addition of Al catalytically accelerates the hydrogen release at 200 °C. In the subsequent cycles, the formation of a new phase of unknown nature is probably responsible for both increased equilibrium hydrogen pressure and decreased dehydrogenation rate. In contrast, AlCl3 additive reacts with LiNH2-MgH2 through the milling and continues during heating under hydrogen pressure. Addition of AlCl3 leads to the formation of two cubic structures identified in the Li-Al-N-H-Cl system, which improves dehydrogenation rate by modifying the thermodynamic stability of the material. This study evidences positive effect of cation and/or anion substitution on hydrogen storage properties of the Li-Mg-N-H system. 2018-10 info:eu-repo/semantics/article 0925-8388 http://hdl.handle.net/10259/4834 10.1016/j.jallcom.2018.06.262 eng Journal of Alloys and Compounds. 2018, V. 765, p. 635–643 https://doi.org/10.1016/j.jallcom.2018.06.262 http://creativecommons.org/licenses/by-nc-nd/4.0/ info:eu-repo/semantics/openAccess Attribution-NonCommercial-NoDerivatives 4.0 International Elsevier