First‐principle investigation of XSrH₃ (X = K and Rb) perovskite‐type hydrides for hydrogen storage

Abstract

Hydrogen can be utilized as an energy source; therefore, hydrogen storage has received the most appealing examination interest in recent years. The investigations of hydrogen storage applications center fundamentally around the examination of hydrogen capacity abilities of recently presented compounds. XSrH 3 (X = K and Rb) compounds have been examined by density functional theory (DFT) calculations to uncover their different characteristics, as well as hydrogen capacity properties, for the first time. Studied compounds are optimized in the cubic phase, and optimized lattice constants are obtained as 4.77 and 4.99 Å for KSrH 3 and RbSrH 3 , respectively. These hydrides have shown negative values of formation enthalpies as they are stable thermodynamically. XSrH 3 might be used in hydrogen storage applications because of high gravimetric hydrogen storage densities, which are 2.33 and 1.71 wt% for KSrH 3 and RbSrH 3 , respectively. Moreover, electronic properties confirm the semiconductor nature of these compounds having indirect band gaps of values 1.41 and 1.23 eV for KSrH 3 and RbSrH 3 , respectively. In addition, mechanical properties from elastic constants such as Young modulus and Pugh's ratio, also have been investigated, and these compounds were found to satisfy born stability conditions. Furthermore, Pugh's ratio and Cauchy pressure show that these hydrides have a brittle nature. Furthermore, thermodynamic properties such as entropy and Debye temperature have been examined using the quasiharmonic Debye model for different temperatures and pressures.

Crystal graph attention networks for the prediction of stable materials

“…There are several semiconductors in this list, reaching a maximum PBE gap of 2.43 eV for BaYO 2 H. Last, we find 49 hydrohalides compounds with a +1 metal in the A position (either an alkali or Tl) and a +2 metal in the B position. There are also several hydride perovskites with similar compositions that were previously studied experimentally and computationally ( 60 ), suggesting the possibility of the exchange of the hydrogen by a halide ion. These are nonmagnetic and can have rather large bandgaps reaching a maximum of 5.39 eV (in the PBE approximation) for KMgF 2 H.…”

A DFT investigation on structural, electronic, magnetic, optical, elastic and hydrogen storage properties of Ru-based hydride-perovskites XRuH3 (X = Cr, V, Ni)

“…Recently, perovskite hydrides have garnered attention for hydrogen storage applications. 9,10 Adhering to the ABX 3 formula, 10,11 with A and B representing cations and X denoting an anion, these materials prove adaptable. The anion X can be interchanged with oxygen as well as nitrogen and we can also change it with halogens and uorine, 12,13 rendering perovskite hydrides a versatile solution for hydrogen storage.…”

First principal calculations of electronic, optical and magnetic properties of cubic K1−xYxNbO3(Y = Fe, Ni)

“…It has the structure of rhombohedral perovskite with the group R3c space, which can further enhance its ferroelectric properties by introducing dopants such as iron and nickel with partially filled d sub-shell atom or incomplete d sub-shell cations [9,10]. Scientists may designate a d-block 'transition metal' as part of the periodic table that comprises the 3-12 groups on the periodic table.…”