Effect of Ni concentration on the structural and hydrogen storage characteristics of Zr–Mn based laves phase system

Abstract

The present communication reports the hydrogen storage characteristics of ZrMn 2-x Ni x laves phase hydrides. It is observed that promising hydrogen storage materials can be tailored when ''x'' is in the range of 1.5 B x C 1. The materials formed within this range reversibly store *2 to *3 H/F.U. under manageable operating conditions. The composition ZrMn 0.5 Ni 1.5 is found to absorb and desorb hydrogen under room temperature. The other two compositions ZrMn 0.75 Ni 1.25 and ZrMnNi absorb *3.6 H/F.U. and release *3 and *3.2 H/F.U., respectively. In each case, almost half of the effective storage capacity of total can be reversibly stored within 5 s under room temperature. Therefore, the materials falling within the range of 1.5 B x C 1 are promising candidates for stationary device applications. The correlation between the compositions, structural-microstructural features and thermodynamic data are presented.

Interstitial hydrogen in Laves phases – local electronic structure modifications from first-principles

“…Our results are in agreement with the experimental ndings of Kumar and coworkers. 12 On the other hand, present computational and previous experimental results contradict the rstprinciples calculations conducted on hypothetical ZrMn 2 H 0.5 , 1 for which the authors obtained negative formation enthalpies. In addition, it is expected that the formation of hydrides in Zr-Ni system would be less probable with increasing Ni content, given that Ni, being the late transition metal, does not form stable binary hydride, while Zr does (ZrH 2 ).…”

“…1,7 Furthermore, optimization of the synthesis process of compounds in the Zr-Ni phase system led to the potential discovery of C15 Laves phase ZrNi 2 . Recently, Kumar et al 12 studied the effect of various concentrations of Ni on the ZrMn 2Àx Ni x phase transformation from hexagonal C14 ZrMn 2 to cubic C15 ZrNi 2 compound, and revealed the existence of cubic Laves phase ZrNi 2 . Acknowledging the previous studies,…”

Retrospect on Zirconium Laves Phases ZrZn2 and ZrAl2 with Their Physicochemical Properties and Perspective for Possible Hydrogen Storage Reactions

“…Zirconium alloys are known to have a good corrosion resistance and its incorporation in intermetallic alloys or adjunct substitution provides improved protection against oxide growth depending on alloying concentration (Féron, 2012;Samaras, 2011). This makes Zr-based alloys valuable for different applications like solid-gas reactions or others hydrothermal energy conversions (Mine et al, 2014;Kumarn et al, 2013;Lototskyy et al, 2018;Matsuyama et al, 2018).…”

Enhancing Hydrogen Storage Properties of MgH2 by Transition Metals and Carbon Materials: A Brief Review

“…To overcome above challenges, alloying (Bououdina and Guo, 2002 ; Liao et al, 2004 ; Kumar et al, 2013 ; Xu et al, 2018 ; Ali et al, 2019 ), nanostructuring (Chen et al, 2012 , 2018 ; Yu et al, 2014 ; Sterl et al, 2018 ), nanoconfinement (Nielsen et al, 2009 ; Gosalawit-Utke et al, 2011 ; Jeon et al, 2011 ; Konarova et al, 2013 ; He et al, 2015 ), and doping with catalysts (Su et al, 2016 ; Sun et al, 2016 ; Zhang et al, 2018 ; Pluengphon et al, 2019 ; Wang et al, 2019 ) have been adopted to enhance the hydrogen storage properties of MgH 2 . According to recent studies, the transition metals (Ti, Fe, Co, Ni, Mn, Nb, V, Zr, etc.)…”