Hydrogenation and microstructural properties of hydriding combustion synthesized Mg-Ni-C composite ball-milled with NbF5 catalyst

Muralidhar G. Chourashiya, Yong Han Kim, Choong Nyeon Park, Chan Jin Park*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

The present investigation evaluates the effect of milling the hydriding combustion synthesized (HCSed) MgNiC composite with NbF5 catalyst. X-ray analysis revealed that h-Mg-(1 0 1) peak positions of the ball-milled samples shifted by an amount that varied with the milling time. Morphologically, among the SPEX ball-milled samples the samples with the NbF5 catalyst showed slightly delayed refinement/agglomeration with milling time which was attributed to lubricating-behavior of NbF5 during milling. The final products from both (planetary and SPEX) ball mills showed insignificant agglomeration. A general trend of decreasing surface area with increasing milling time was observed. The HCSed sample manually mixed with catalyst showed the largest surface area of 23.78 m2/g. The presence of the catalyst and different interfaces, such as Mg-Nb, Mg-Ni and Mg-CNTs, in the samples played a crucial role in decreasing the thermal constraints for dehydrogenation. Analysis of hydrogenation kinetics revealed that the catalyst added samples requires activation and can be easily activated. By relating the hydrogenation kinetic data with the JMAK model, the value of the reaction order, n, was found to be close to 1 for all the samples, suggesting a possible diffusional phase transition. The lowest activation energy observed in synthesized sample for hydrogenation was 64.9 kJ/mol.

Original languageEnglish
Pages (from-to)47-55
Number of pages9
JournalJournal of Alloys and Compounds
Volume584
DOIs
StatePublished - 2014
Externally publishedYes

Keywords

  • Hydrogen storage
  • Mechanical milling
  • Mg-based alloys
  • NbF -catalyst
  • XRD

Fingerprint Dive into the research topics of 'Hydrogenation and microstructural properties of hydriding combustion synthesized Mg-Ni-C composite ball-milled with NbF<sub>5</sub> catalyst'. Together they form a unique fingerprint.

Cite this