摘要
Li-Mg-N-B-H/ZrCoH_(3) composites were successfully synthesized by ball milling of the reactants under argon and hydrogen atmosphere,respectively.The composite synthesized by reactive ball milling(RBM)under hydrogen has the best hydrogen storage properties.It can desorb 3.71 wt%hydrogen in 60 min at 150℃under pressure of 0.1 MPa,and the dehydrogenation capacity reaches 4.59 wt%in 8 h.For the re-hydrogenation,5.27 wt%hydrogen was absorbed in only 10 min at 150℃under H_(2) pressure of 8 MPa.The phases of the as-milled and subsequently dehydrogenated and re-hydrogenated samples were determined by X-ray diffraction(XRD).The microstructures and elemental distributions were characterized by scanning electron microscope(SEM)and energy-dispersive spectrometer(EDS)measurements.It is shown that Mg is in situ hydrogenated and introduced homogeneous distribution of ZrCoH_(3) particles during the RBM process under hydrogen atmosphere.The activation energies for the composites were calculated by Kissinger method through differential scanning calorimetric(DSC)measurements for the dehydrogenation process with different heating rates.It is determined that the activation energy for the Li-Mg-N-B-H/ZrCoH_(3) composite synthesized by RBM under hydrogen is 79.9 kJ·mol^(-1),which is14 kJ·mol^(-1) lower than that for the sample without ZrCoH_(3) addition.The N-H bond energies were analyzed by infrared(IR)absorption spectrum,and the reasons for weakening of the N-H bond were further discussed.
出处
《Rare Metals》
SCIE
EI
CAS
CSCD
2023年第3期1036-1042,共7页
稀有金属(英文版)
基金
financially supported by Beijing Science and Technology Program(No.D141100002014002)。