In situ formation of LDH membranes of different microstructures with molecular sieve gas selectivity

authored by
Yi Liu, Nanyi Wang, Jürgen Caro
Abstract

Research on interlayer gallery-based gas and liquid separation has gained widespread attention. A series of layered materials like lamellar ZSM-5, graphene and its derivatives have been fabricated into membranes showing fascinating gas/liquid separation properties. Layered double hydroxides (LDHs) are prominent representatives of layered compounds composed of regularly arranged brucite-like 2D sheets. Here we successfully prepared well-intergrown NiAl-CO3 LDH membranes in one step. Particularly it was found that CO2 dissolved in the precursor solution exerted great influence on the microstructure of prepared membranes. Trace amounts of CO2 in the precursor solution led to the formation of ab-oriented 0.6 μm thick LDH membranes, while randomly oriented 5 μm thick LDH membranes formed from CO2-saturated precursor solutions. Both ab- & randomly oriented LDH membranes showed clear size-based selectivity and H2 was found to preferentially permeate through the interlayer galleries. However, randomly oriented LDH membranes showed a much higher H2 selectivity possibly due to the decreased density of mesoscopic defects. Furthermore, in addition to the NiAl-CO3 LDH membrane, a compact and randomly oriented ZnAl-NO3 LDH membrane with reasonable gas selectivity was successfully prepared here by proper optimization of the synthesis conditions.

Organisation(s)
Institute of Physical Chemistry and Electrochemistry
Type
Article
Journal
Journal of Materials Chemistry A
Volume
2
Pages
5716-5723
No. of pages
8
ISSN
2050-7488
Publication date
2014
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
General Chemistry, Renewable Energy, Sustainability and the Environment, General Materials Science
Sustainable Development Goals
SDG 7 - Affordable and Clean Energy
Electronic version(s)
https://doi.org/10.1039/c4ta00108g (Access: Closed)
https://doi.org/10.15488/116 (Access: Open)