Synthesis and decomposition mechanisms of ternary Mg2COH5 studied using in situ synchrotron X-ray diffraction
(2011) In International Journal of Hydrogen Energy 36(17). p.10760-10770- Abstract
- A ternary Mg2COH5 hydride was synthesized using a novel method that relies on a relatively short mechanical milling time (1 h) of a 2:1 MgH2-Co powder mixture followed by sintering at a sufficiently high hydrogen pressure (>85 bar) and heating from RT to 500 degrees C. The ternary hydride forms in less than 2.5 h (including the milling time) with a yield of similar to 90% at similar to 300 degrees C. The mechanisms of formation and decomposition of ternary Mg2COH5 were studied in detail using an in situ synchrotron radiation powder X-ray diffraction (SR-PXD). The obtained experimental results are supported by morphological and microstructural investigations performed using SEM and high-resolution STEM. Additionally, thermal effects... (More)
- A ternary Mg2COH5 hydride was synthesized using a novel method that relies on a relatively short mechanical milling time (1 h) of a 2:1 MgH2-Co powder mixture followed by sintering at a sufficiently high hydrogen pressure (>85 bar) and heating from RT to 500 degrees C. The ternary hydride forms in less than 2.5 h (including the milling time) with a yield of similar to 90% at similar to 300 degrees C. The mechanisms of formation and decomposition of ternary Mg2COH5 were studied in detail using an in situ synchrotron radiation powder X-ray diffraction (SR-PXD). The obtained experimental results are supported by morphological and microstructural investigations performed using SEM and high-resolution STEM. Additionally, thermal effects occurring during the desorption reaction were studied using DSC. The morphology of as-prepared ternary Mg2COH5 is characterized by the presence of porous particles with various shapes and sizes, which, in fact, are a type of nanocomposite consisting mainly of nanocrystallites with a size of similar to 5 nm. Mg2COH5 decomposes at approximately 300 degrees C to elemental Mg and Co. Additionally, at approximately 400 degrees C, MgCo is formed as precipitates inserted into the Mg Co matrix. During the rehydrogenation of the decomposed residues, prior to the formation of Mg2COH5, MgH2 appears, which confirms its key role in the synthesis of the ternary Mg2COH5. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/2208317
- author
- Norek, M. ; Nielsen, T. K. ; Polanski, M. ; Kunce, I. ; Plocinski, T. ; Jaroszewicz, L. R. ; Cerenius, Yngve LU ; Jensen, T. R. and Bystrzycki, J.
- organization
- publishing date
- 2011
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Magnesium-cobalt hydride, Synthesis, Mechanical milling, In situ, SR-PXD, Microstructure
- in
- International Journal of Hydrogen Energy
- volume
- 36
- issue
- 17
- pages
- 10760 - 10770
- publisher
- Elsevier
- external identifiers
-
- wos:000295235200035
- scopus:80051602061
- ISSN
- 1879-3487
- DOI
- 10.1016/j.ijhydene.2011.05.126
- language
- English
- LU publication?
- yes
- id
- b5fd1f4c-2652-4285-bb18-ff5b3b37f1be (old id 2208317)
- date added to LUP
- 2016-04-01 14:19:11
- date last changed
- 2022-03-21 23:23:07
@article{b5fd1f4c-2652-4285-bb18-ff5b3b37f1be,
abstract = {{A ternary Mg2COH5 hydride was synthesized using a novel method that relies on a relatively short mechanical milling time (1 h) of a 2:1 MgH2-Co powder mixture followed by sintering at a sufficiently high hydrogen pressure (>85 bar) and heating from RT to 500 degrees C. The ternary hydride forms in less than 2.5 h (including the milling time) with a yield of similar to 90% at similar to 300 degrees C. The mechanisms of formation and decomposition of ternary Mg2COH5 were studied in detail using an in situ synchrotron radiation powder X-ray diffraction (SR-PXD). The obtained experimental results are supported by morphological and microstructural investigations performed using SEM and high-resolution STEM. Additionally, thermal effects occurring during the desorption reaction were studied using DSC. The morphology of as-prepared ternary Mg2COH5 is characterized by the presence of porous particles with various shapes and sizes, which, in fact, are a type of nanocomposite consisting mainly of nanocrystallites with a size of similar to 5 nm. Mg2COH5 decomposes at approximately 300 degrees C to elemental Mg and Co. Additionally, at approximately 400 degrees C, MgCo is formed as precipitates inserted into the Mg Co matrix. During the rehydrogenation of the decomposed residues, prior to the formation of Mg2COH5, MgH2 appears, which confirms its key role in the synthesis of the ternary Mg2COH5. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.}},
author = {{Norek, M. and Nielsen, T. K. and Polanski, M. and Kunce, I. and Plocinski, T. and Jaroszewicz, L. R. and Cerenius, Yngve and Jensen, T. R. and Bystrzycki, J.}},
issn = {{1879-3487}},
keywords = {{Magnesium-cobalt hydride; Synthesis; Mechanical milling; In situ; SR-PXD; Microstructure}},
language = {{eng}},
number = {{17}},
pages = {{10760--10770}},
publisher = {{Elsevier}},
series = {{International Journal of Hydrogen Energy}},
title = {{Synthesis and decomposition mechanisms of ternary Mg2COH5 studied using in situ synchrotron X-ray diffraction}},
url = {{http://dx.doi.org/10.1016/j.ijhydene.2011.05.126}},
doi = {{10.1016/j.ijhydene.2011.05.126}},
volume = {{36}},
year = {{2011}},
}