Jump to main content
Jump to site search

Issue 33, 2017
Previous Article Next Article

The cycling stability of the in situ formed Mg-based nanocomposite catalyzed by YH2

Author affiliations

Abstract

Long cycling life is one prerequisite for the commercial application of hydrogen storage materials. The cycling stability of a promising Mg + Mg2Ni + YH2 hydrogen storage nanocomposite made by hydrogen-induced decomposition of the 18R-type long period stacking ordered (LPSO) structure is investigated. At 300 °C, it absorbs maximum ∼5.2 wt% H at the 40th de/hydrogenation cycle and still has 4.3 wt% H even after 620 cycles. Both activation and passivation occur during the 40th–620th cycles, where the absorption rate within 0–15 s becomes faster but the rate after 15 s gradually slows down. Characterizations by synchrotron X-ray powder diffraction and transmission electron microscopy reveal that this phenomenon is closely related to the pulverization of particles and the aggregation of YH2 nanocatalysts. From the first-principles calculations, the catalytic effect of YH2 is ascribed to the relatively high interfacial energy of YH2/Mg, the low diffusion energy barrier for H at the YH2/Mg interface, and the high affinity between YH2 and H. 17% loss of hydrogen capacity is attributed to the formation of kinetically inactive Mg/MgH2 phases, the aggregation of YH2 and the oxidation of Mg. Minimizing the separation between the Mg/MgH2 matrix and YH2 nanocatalysts is crucial to maintain the high effective capacity of this nanocomposite.

Graphical abstract: The cycling stability of the in situ formed Mg-based nanocomposite catalyzed by YH2

Back to tab navigation

Supplementary files

Publication details

The article was received on 25 May 2017, accepted on 26 Jul 2017 and first published on 26 Jul 2017


Article type: Paper
DOI: 10.1039/C7TA04551D
Citation: J. Mater. Chem. A, 2017,5, 17532-17543
  •   Request permissions

    The cycling stability of the in situ formed Mg-based nanocomposite catalyzed by YH2

    Q. Li, Y. Li, B. Liu, X. Lu, T. Zhang and Q. Gu, J. Mater. Chem. A, 2017, 5, 17532
    DOI: 10.1039/C7TA04551D

Search articles by author

Spotlight

Advertisements