Catalytic effect of additives on the hydrogen absorption properties of nano-crystalline MgH2(X) composites

Dehydrogenation kinetics of pure and nickel-doped magnesium hydride investigated by in situ time-resolved powder X-ray diffraction

“…Thermodynamics dictate that relatively high temperatures (T > 280 • C) must be applied to desorb H 2 from pure MgH 2 due to a formation enthalpy of MgH 2 of, H f = −75 kJ/mol [4]. Furthermore, investigations have shown that kinetics can be improved remarkably either by reduction of the particle size by ball milling, by mechanical alloying or sputter deposition of other elements or by doping with carbon [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. In this way, the kinetics can be improved by reducing the diffusion path of hydrogen atoms in Mg and MgH 2 , facilitating the diffusion process or by adding catalysts on the metal surface for the dissociation or formation of H 2 molecules.…”

Atomic Hydrogen Diffusion in Novel Magnesium Nanostructures: The Impact of Incorporated Subsurface Carbon Atoms

“…Unfortunately, the application is primarily limited by the high hydrogenation reaction temperature and slow kinetics [4][5]. Experimentally, a number of studies have been devoted to the catalytic effect on hydrogen adsorption of mixing transition metals into the Mg powder by mechanical milling [6][7][8]. Apart from metallic alloying, some non-metallic elements such as graphitic carbon have been noted to facilitate the activation process of Mg and improve the absorption kinetics of H 2 [9][10][11][12][13].…”

The role of V2O5 on the dehydrogenation and hydrogenation in magnesium hydride: An ab initio study

“…[4][5][6] Experimentally, many studies have been devoted to the catalytic effect on hydrogen adsorption of mixing transition metals or their oxides in small quantities into Mg hydride powder during ball milling. [7][8][9][10] The transition metals, such as Ti, Nb, V, etc. are believed to act as catalysts for enhancing the surface dissociation of molecular hydrogen into adsorbed atoms, [11][12][13][14][15] 17 Clearly, the use of a cheap metal oxide compared to the pure metal for catalytic purposes is an advantage from the cost perspective.…”