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A novel process has been developed to synthesize MgH2 nanoparticles by combining ball milling and thermal hydrogenolysis of di-n-butylmagnesium (C4H9)2Mg, denoted as MgBu2. With the aid of mechanical impact, the hydrogenolysis temperature of MgBu2 in heptane and cyclohexane solution was considerably lowered down to 100 °C, and the MgH2 nanoparticles with an average particle size of ca. 8.9 nm were obtained without scaffolds. The nano-size effect of the MgH2 nanoparticles causes a notable decrease in the onset dehydrogenation temperature of 225 °C and enthalpy of 69.78 kJ mol−1 · H2. This thermally-assisted milling and hydrogenolysis process may also be extended for synthesizing other nanomaterials. [ABSTRACT FROM AUTHOR]

This paper reported that the transmission of hydrogenated Mg–La films is influenced by the content of La dissolved in Mg. With the increase in La:Mg atomic ratio, the transmission decreases and the short wavelength limit of the transmission spectra shifts toward the long wavelength side. This phenomenon is well explained by using the Lambert–Beer law according to the band gap change, which was calculated using CASTEP module caused by dissolving of La. [ABSTRACT FROM AUTHOR]

In order to improve the high-rate discharge properties of La11.3Mg6.0Sm7.4Ni61.0Co7.2Al7.1(AB3.0) alloy electrodes, the effects of plasma milling (PM) and graphene addition on their electrochemical properties and kinetics have been investigated. It was found that the discharge capacity of AB3.0 at a high discharge current density was significantly improved after the addition of graphene followed by PM for only 10 min. Moreover, the high-rate dischargeability (HRD) and the exchange current density I0 of the alloy electrodes were also increased. The PM technique exhibits obvious advantages for improving the high-rate discharge properties of hydrogen-storage alloys. [ABSTRACT FROM AUTHOR]

A Mg9Ag alloy is employed as a medium for both production of hydrogen and preparation of Ag nanoparticles through hydrolysis. Mg9Ag milled under H2 exhibits very favorable structural characteristics, i.e., yielding a fine nanocrystal powder and partial hydrogen-induced phase decomposition. As a result, a hydrogen yield of 730 mL g-1 is obtained in 25 min at 298 K, a much higher rate than produced by samples not milled or milled under argon. Moreover, the hydrolysis by-product can be recycled to obtain Ag nanoparticles by removing insoluble Mg(OH)2 using an added HCl solution. These results show that this process provides a highly efficient method for economically produce hydrogen and Ag nanoparticles. [ABSTRACT FROM AUTHOR]

A novel process has been developed to synthesize MgH 2 nanoparticles by combining ball milling and thermal hydrogenolysis of di- n -butylmagnesium (C 4 H 9 ) 2 Mg, denoted as MgBu 2 . With the aid of mechanical impact, the hydrogenolysis temperature of MgBu 2 in heptane and cyclohexane solution was considerably lowered down to 100 °C, and the MgH 2 nanoparticles with an average particle size of ca. 8.9 nm were obtained without scaffolds. The nano-size effect of the MgH 2 nanoparticles causes a notable decrease in the onset dehydrogenation temperature of 225 °C and enthalpy of 69.78 kJ mol -1  · H 2 . This thermally-assisted milling and hydrogenolysis process may also be extended for synthesizing other nanomaterials., (© 2021 IOP Publishing Ltd.)

Multi-layer hydrogen storage thin films with Mg and MmNi3.5(CoAlMn)1.5 (here Mm denotes La-rich mischmetal) as alternative layers were prepared by direct current magnetron sputtering. Transmission electron microscopy investigation shows that the microstructure of the MmNi3.5(CoAlMn)1.5 and Mg layers are significantly different although their deposition conditions are the same. The MmNi3.5(CoAlMn)1.5 layer is composed of two regions: one is an amorphous region approximately 4 nm thick at the bottom of the layer and the other is a nanocrystalline region on top of the amorphous region. The Mg layer is also composed of two regions: one is a randomly orientated nanocrystalline region 50 nm thick at the bottom of the layer and the other is a columnar crystallite region on top of the nanocrystalline region. These Mg columnar crystallites have their [001] directions parallel to the growth direction and the average lateral size of these columnar crystallites is about 100 nm. A growth mechanism of the multi-layer thin films is discussed based on the experiment results., (2004 Wiley-Liss, Inc.)