Sonwabo E. Bambalaza
Experimental Demonstration of Dynamic Temperature-Dependent Behavior of UiO-66 Metal–Organic Framework: Compaction of Hydroxylated and Dehydroxylated Forms of UiO-66 for High-Pressure Hydrogen Storage
Bambalaza, Sonwabo E.; Langmi, Henrietta W.; Mokaya, Robert; Musyoka, Nicholas M.; Khotseng, Lindiwe E.
Authors
Henrietta W. Langmi
Robert Mokaya
Nicholas M. Musyoka
Lindiwe E. Khotseng
Abstract
High-pressure (700 MPa or ∼100 000 psi) compaction of dehydroxylated and hydroxylated UiO-66 for H2 storage applications is reported. The dehydroxylation reaction was found to occur between 150 and 300 °C. The H2 uptake capacity of powdered hydroxylated UiO-66 reaches 4.6 wt % at 77 K and 100 bar, which is 21% higher than that of dehydroxylated UiO-66 (3.8 wt %). On compaction, the H2 uptake capacity of dehydroxylated UiO-66 pellets reduces by 66% from 3.8 to 1.3 wt %, while for hydroxylated UiO-66 the pellets show only a 9% reduction in capacity from 4.6 to 4.2 wt %. This implies that the H2 uptake capacity of compacted hydroxylated UiO-66 is at least three times higher than that of dehydroxylated UiO-66, and therefore, hydroxylated UiO-66 is more promising for hydrogen storage applications. The H2 uptake capacity is closely related to compaction-induced changes in the porosity of UiO-66. The effect of compaction is greatest in partially dehydroxylated UiO-66 samples that are thermally treated at 200 and 290 °C. These compacted samples exhibit XRD patterns indicative of an amorphous material, low porosity (surface area reduces from between 700 and 1300 m2/g to ca. 200 m2/g and pore volume from between 0.4 and 0.6 cm3/g to 0.1 and 0.15 cm3/g), and very low hydrogen uptake (0.7–0.9 wt % at 77 K and 100 bar). The observed activation-temperature-induced dynamic behavior of UiO-66 is unusual for metal–organic frameworks (MOFs) and has previously only been reported in computational studies. After compaction at 700 MPa, the structural properties and H2 uptake of hydroxylated UiO-66 remain relatively unchanged but are extremely compromised upon compaction of dehydroxylated UiO-66. Therefore, UiO-66 responds in a dynamic manner to changes in activation temperature within the range in which it has hitherto been considered stable.
Journal Article Type | Article |
---|---|
Acceptance Date | May 11, 2020 |
Online Publication Date | May 11, 2020 |
Publication Date | Jun 3, 2020 |
Deposit Date | Jun 18, 2020 |
Publicly Available Date | May 12, 2021 |
Journal | ACS Applied Materials & Interfaces |
Print ISSN | 1944-8244 |
Electronic ISSN | 1944-8252 |
Publisher | American Chemical Society |
Peer Reviewed | Peer Reviewed |
Volume | 12 |
Issue | 22 |
Pages | 24883-24894 |
DOI | https://doi.org/10.1021/acsami.0c06080 |
Public URL | https://nottingham-repository.worktribe.com/output/4672839 |
Publisher URL | https://pubs.acs.org/doi/10.1021/acsami.0c06080 |
Additional Information | This document is the Accepted Manuscript version of a Published Work that appeared in final form in : ACS Applied Materials and Interfaces,copyright ©American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acsami.0c06080 |
Files
RMokaya Experimental Demonstration Of Dynamic
(643 Kb)
PDF
Downloadable Citations
About Repository@Nottingham
Administrator e-mail: discovery-access-systems@nottingham.ac.uk
This application uses the following open-source libraries:
SheetJS Community Edition
Apache License Version 2.0 (http://www.apache.org/licenses/)
PDF.js
Apache License Version 2.0 (http://www.apache.org/licenses/)
Font Awesome
SIL OFL 1.1 (http://scripts.sil.org/OFL)
MIT License (http://opensource.org/licenses/mit-license.html)
CC BY 3.0 ( http://creativecommons.org/licenses/by/3.0/)
Powered by Worktribe © 2024
Advanced Search