Synthesis and hydrogen storage properties of Mg–La–Al nanoparticles

Remarkable hydrogen storage properties at low temperature of Mg–Ni composites prepared by hydriding combustion synthesis and mechanical milling

“…The experimental results have demonstrated that the hydrogen storage properties of Mg-Ni composites are considerably enhanced compared with pure Mg. To further understand the dehydriding kinetics mechanism, the Johnson-Mehl-Avrami (JMA) kinetic model was used to describe the hydrogen desorption. 32,33 The Mg 90 Ni 10 with relatively better properties was chosen to further study. The equation of JMA model is presented below:…”

Catalytic Effects of Decorating AlV3 Nanocatalyst on Hydrogen Storage Performance of Mg@Mg17Al12 Nanocomposite: Experimental and Theoretical Study

“…Adding catalysts to promote the hydrogen dissociation–diffusion–recombination process, combined with nanosizing of Mg particles to shorten the hydrogen diffusion distance and tune thermodynamics, is the main way for improving hydrogen storage properties. , In the last few decades, numerous transition metals with 3d orbits, such as Ni, Ti, V, Fe, etc., their oxides, − carbides, , borides, and other compounds , have been designed by various approaches. In particular, recent theoretical and experimental results imply that the kinetic performance and operating temperatures of Mg-based materials can be improved by catalysts with multiple phases or structures. , Vanadium-based catalysts are suggested to be one of the most effective ones, which show significant positive effects on the kinetics of Mg, even added with a small percentage. , Liu et al prepared V-decorated Mg nanoparticles (NPs) by the hydrogen plasma metal reaction (HPMR) approach and found that its storage capacity reached 3.7 wt % within 30 min at a low temperature of 473 K . Studies show that the partial V 2 O 3 phase would be reduced to metallic V during the ball milling process, which can significantly weaken the Mg–H bond energy, leading to the lower desorption temperature and better sorption kinetics.…”

“…The in situ formed Mg 2 V 2 O 7 , V 2 O 3 , and Bi 2 O 3 multiple catalysts from the reaction of BiVO 4 with Mg show synergistic effects on the decrease of the hydrogen dissociation energy barrier of hydrogen and thus improve the kinetic performance of Mg. Furthermore, reports show that Al-transition metal compounds used as catalyst additives can also tune the hydrogen absorption/desorption kinetics of Mg particles. , The pure LaH 3 and Al can be in situ obtained from the decomposition of Al 2 La in the absorption process; then the Al would dissolve into Mg, while LaH 3 always shows catalytic activation in the later cycling process . The Ni–Al compounds in the La 2 Mg 17 alloy were proved to be high activation catalysts for improving kinetics and decreasing the hydrogen absorption activation energy.…”

“…In particular, recent theoretical and experimental results imply that the kinetic performance and operating temperatures of Mg-based materials can be improved by catalysts with multiple phases or structures. 26,27 Vanadium-based catalysts are suggested to be one of the most effective ones, which show significant positive effects on the kinetics of Mg, even added with a small percentage. 15,28 Liu et al prepared V-decorated Mg nanoparticles (NPs) by the hydrogen plasma metal reaction (HPMR) approach and found that its storage capacity reached 3.7 wt % within 30 min at a low temperature of 473 K. 29 Studies show that the partial V 2 O 3 phase would be reduced to metallic V during the ball milling process, 16 which can significantly weaken the Mg−H bond energy, leading to the lower desorption temperature and better sorption kinetics.…”

“…Furthermore, reports show that Al-transition metal compounds used as catalyst additives can also tune the hydrogen absorption/ desorption kinetics of Mg particles. 26,31 The pure LaH 3 and Al can be in situ obtained from the decomposition of Al 2 La in the absorption process; then the Al would dissolve into Mg, while LaH 3 always shows catalytic activation in the later cycling process. 26 The Ni−Al compounds in the La 2 Mg 17 alloy 31 were proved to be high activation catalysts for improving kinetics and decreasing the hydrogen absorption activation energy.…”