Abstract
Herein, we demonstrate that tuning of structural parameters and material chemistry enables control of the permeability and selectivity of gases (CO2, He, and CH4) in membranes based on poly(butyl methacrylate)-grafted nanoparticles (PGNs). Our data show that the presence of nanoparticles and the overall dense packing of grafted chains noticeable in PGNs with low grafting density have an adverse effect on the diffusivity of gases. This effect is compensated by an improvement in the solubility of CO2 gas promoted by the silica nanoparticle surface, yielding a substantial improvement in the permeability of CO2 versus CH4. In membranes with high grafting density, changes in the structural arrangements and alterations in the membrane porosity, evident from small-angle X-ray scattering and positron annihilation lifetime spectroscopy, positively influence the permeability of He and CO2 gases. In contrast, CH4 permeability in the same membranes is significantly suppressed, suggesting the formation of a unique, highly selective environment for gas separation. As a result, an improvement of up to 50% in selectivity for gas pairs containing large CH4 molecules is observed. Our studies provide fundamental insights into the role that structural parameters play in gas transport through polymer membranes, laying a foundation for the rational design of membranes with improved permeability and selectivity.
| Original language | English |
|---|---|
| Pages (from-to) | 5895-5903 |
| Number of pages | 9 |
| Journal | ACS Applied Nano Materials |
| Volume | 4 |
| Issue number | 6 |
| DOIs | |
| State | Published - Jun 25 2021 |
Funding
This work was supported by the Laboratory Directed Research and Development program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the US Department of Energy (DOE). I.P. acknowledges partial financial support from the DOE Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division for data analysis. R.K. acknowledges support from the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. S.M. was supported by the Division of Chemical Sciences, Geosciences, and Biosciences, Office of Basic Energy Sciences, U.S. Department of Energy. We would like to thank Dr. Karsten Joensen for help with X-ray measurements and Dr. Tolga Aytug for help with NPs dissolution. This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the US Department of Energy (DOE). The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ). Acknowledgments
| Funders | Funder number |
|---|---|
| Center for Nanophase Materials Sciences | |
| U.S. Department of Energy | |
| Office of Science | |
| Basic Energy Sciences | |
| Oak Ridge National Laboratory | |
| Chemical Sciences, Geosciences, and Biosciences Division |
Keywords
- gas transport
- hairy nanoparticles
- membranes
- permeability
- polymer-grafted nanoparticles
- polymers
- selectivity