The invention relates to the technical field of
hydrogen storage materials, in particular to a doped symbiotic LaH2.46-La2O3 ultra-
fine grain low-temperature reversible
hydrogen absorption and
desorption magnesium-based composite
hydrogen storage material as well as a preparation method and application thereof. The preparation method comprises the following steps: preparing LaH < 2.46-La >
powder; the LaH < 2.46-La >
powder is subjected to ball milling under the
air atmosphere, and symbiotic LaH < 2.46-La2O3
powder is prepared; the preparation method comprises the following steps: carrying out ball milling on the symbiotic LaH < 2.46 >-La2O3 powder, Mg powder and Ni powder in an
argon atmosphere to prepare nano composite powder; hydrotreating the composite powder; carrying out
dehydrogenation treatment on the hydrogenated composite powder; the composite powder hydrogenation step and the hydrogenated composite powder
dehydrogenation step are sequentially and repeatedly circulated for multiple times, and the composite powder is obtained. According to the scheme, excellent dynamic performance and
cycling stability are achieved, and the
composite material can be used as a
hydrogen storage medium, can be used as an
active medium for storing and transporting hydrogen in a
solid-state
hydrogen storage device, has the characteristics of high
hydrogen storage density, relatively low
hydrogen absorption and
desorption temperature, good
hydrogen absorption and
desorption cycling stability, high safety, environment friendliness, low cost and the like, and has wide application prospects. And the application is not limited to a
solid hydrogen storage device and can also be used as a heat exchange medium of a
heat pump.