Structural study and hydrogen sorption kinetics of ball-milled magnesium hydride

Enhanced hydrogen reaction kinetics of nanostructured Mg-based composites with nanoparticle metal catalysts dispersed on supports

“…From the slope of these straight lines, the activation energies of as received MgH 2 and 18 h milled MgH 2 were estimated to be 172.1 and 146.8 kJ/mol, respectively, similar to the reported values (156 and 144 kJ/mol) [25,5]. Even though BCN catalyst was very effective to enhance desorption kinetics at 300 • C [9,10], Ni/Pd metallic catalysts were much effective to enhance sorption kinetics at lower temperature according to DSC data.…”

New FCC Mg–Zr and Mg–Zr–ti deuterides obtained by reactive milling

“…However, the high thermal stability and slow kinetics of its rutile-type structure significantly hinder its widespread use in commercial energy storage systems. Many factors such as a chemical composition [2][3][4] , addition of catalytic species [5][6][7][8][9][10] , processing technologies 5,[11][12][13][14] and microstructural parameters, particularly grain size 6,[15][16][17] , have an effect on the hydrogen storage capacity, kinetics and/or thermodynamics of Mg-based intermetallic compounds. Conventional crystalline alloys often suffer from relatively slow hydrogen sorption kinetics even at high temperatures, while nanocrystalline and amorphous materials exhibit much faster kinetics at lower temperatures, as their large number of interfaces, defects and grain boundaries, provide easy pathways for hydrogen diffusion [18][19][20][21] .…”

Atomistic long-term simulation of heat and mass transport

“…Also in both phases, the hydrogen diffusion coefficient D H is well described by an Arrhenius law in the temperature range of 230 and 900 K. For bulk palladium at room temperature (298 K), D H is measured to be 3.8 × 10 −7 cm 2 /s in α-phase and 2.0 × 10 −7 cm 2 /s in β-phase (Adams and Chen, 2011). Recently, extensive research has been devoted to developing and optimizing metal-based nanomaterials for high-speed, high-capacity, reversible hydrogen storage applications (e. g., Huot et al (1999); Li et al (2007)). For some nanomaterials, particularly nanofilms, Li and Cheng (1996) and Hagi (1990) showed that these diffusivities may decrease by two to four orders of magnitude.…”