ZIF-8 Nanofibers Enhance MOF CO2 Capture Capabilities

In a study available as a pre-proof in the Journal of Membrane Science, a metal organic framework (MOF) transportation channel for carbon dioxide (CO2) with minimal impedance was built in a mixed matrix membrane (MMM) with the help of electrospun nanoscale fibers.

ZIF-8 Nanofibers Enhance MOF CO2 Capture Capabilities

Study: PAN electrospun nanofiber skeleton induced MOFs continuous distribution in MMMs to boost CO2 capture. Image Credit: Horth Rasur/Shutterstock.com

Capturing CO2 with Metal Organic Frameworks

Carbon dioxide, being a major greenhouse gas and a significant resource of carbon, has proven difficult to absorb, harness, and store for sustainable usage.

Compared to classic CO2 extraction techniques such as cryogenic isolation, pressure swing adsorption, and so forth, the membrane separation technique offers a superior potential in capturing CO2 due to its higher efficiency, ease of pairing, and cheap cost, among other advantages.

Among the numerous kinds of CO2 separation screens, mixed matrix membrane (MMM) with synthetic material dispersion in a polymeric matrix is predicted to overcome the trade-off effect of polymeric membrane specificity and permeability.

Gas separating effectiveness in MMM is determined by the inherent characteristics of synthetic fillers and polymers, as well as their interface compliance.

In particular, the synthetic fillers supply gas molecules with extra adsorptive areas and preferred transport routes, allowing for both greater permeation and higher selectivity.

Metal organic frameworks (MOFs) are expected to offer MMM with good gas permeability, strong interface compliance, and hence greater gas selectivity because of their largely organic nature, high porosity, and simple function.

As a result, significant momentum has been achieved in developing MOF-based MMM for CO2 collection.

Issues Faced Due to Discontinuous Distribution of MOFs in Polymeric Matrices

Unfortunately, when specificity is kept constant, the carbon dioxide permeation of MOF-based MMM is merely 1-3x greater than that of conventional polymeric membranes. This figure is significantly lesser than that of a homogeneous MOF membrane.

The irregular dispersion of MOFs in the polymeric framework is primarily responsible for the poor carbon dioxide permeation of MOF-based MMM.

As a result, the passage of gaseous molecules through the barrier is short-circuited and continues to be controlled by the polymer. As a consequence, the elevated carbon dioxide permeability of MOFs is not completely reproduced, resulting in inadequate CO2 permeability augmentation.

If additional MOFs were introduced to the polymeric matrix, it would eventually produce a low-resistance CO2 transfer route across the membrane controlled by MOFs.

As a consequence, MMM's CO2 permeation might be considerably increased. However, when the quantity of MOFs used in MMM exceeds 30 wt%, it is possible to trigger aggregation of MOFs, resulting in poor compatibility among MOFs and polymeric matrix.

As a result, specificity flaws and even phase dissociation develop in MMM, drastically reducing selectivity. Therefore, building a steady and low-inhibition gas transporting route by increasing MOFs packing while maintaining selectivity is incredibly difficult.

Considerable attempts have been made to improve the interface compliance of MOFs with the polymeric matrix.

Although certain advances have been achieved in the construction of MOF transport pathways by boosting their loading, most techniques are not ubiquitous. Furthermore, in these investigations, MOFs were not completely consistent throughout the membrane.

It is critical to investigate a simple and universal technique for achieving continuous dispersion of MOFs in a polymeric matrix.

Important Findings of the Study

In this study, on-site polymerization of PEG within ZIF-8-based electrospun nanofibrous mats was used to create a new MMM with ZIF-8 constantly disseminated in polymeric matrix.

ZIF-8 particles developed steadily on the exterior of PAN nanofibers, and the quantity of ZIF-8 grew in proportion to the growing period. Gas adsorption rose as ZIF-8 content was increased, which was good for CO2 permeability.

The MMM was found to be thick and fault-free, according to the SEM pictures. Significantly, a long-distance and steady ZIF-8 transportation channel was generated across the barrier. Furthermore, the high Tg of [email protected]/PEO MMM by differential scanning calorimetry (DSC) suggested that ZIF-8 and PEO have strong interface compatibility.

According to the gas separation findings, all of the [email protected]/PEO MMMs had increased CO2 permeation but significantly decreased CO2/N2 selectivity when compared to the PAN/PEO NFM. This behavior was most likely caused by the PAN nanofibers' uninterrupted ZIF-8 transportation channel.

The [email protected]/PEO MMM, in particular, had increased CO2 permeation as well as better CO2 selectivity over N2. This was because of the steady ZIF-8 transport channel and the high interface compatibility.

The current study demonstrates a unique and successful method for increasing the CO2 permeability of MOF-based MMM. In the future, porosity engineering of MOFs could allow selectivity to be fine-tuned even further.

Reference

Zheng, W., Li, Z., et al. (2022). PAN electrospun nanofiber skeleton induced MOFs continuous distribution in MMMs to boost CO2 capture. Journal of Membrane Science. Available at: https://www.sciencedirect.com/science/article/pii/S0376738822000783?via%3Dihub

Disclaimer: The views expressed here are those of the author expressed in their private capacity and do not necessarily represent the views of AZoM.com Limited T/A AZoNetwork the owner and operator of this website. This disclaimer forms part of the Terms and conditions of use of this website.

Shaheer Rehan

Written by

Shaheer Rehan

Shaheer is a graduate of Aerospace Engineering from the Institute of Space Technology, Islamabad. He has carried out research on a wide range of subjects including Aerospace Instruments and Sensors, Computational Dynamics, Aerospace Structures and Materials, Optimization Techniques, Robotics, and Clean Energy. He has been working as a freelance consultant in Aerospace Engineering for the past year. Technical Writing has always been a strong suit of Shaheer's. He has excelled at whatever he has attempted, from winning accolades on the international stage in match competitions to winning local writing competitions. Shaheer loves cars. From following Formula 1 and reading up on automotive journalism to racing in go-karts himself, his life revolves around cars. He is passionate about his sports and makes sure to always spare time for them. Squash, football, cricket, tennis, and racing are the hobbies he loves to spend his time in.

Citations

Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Rehan, Shaheer. (2022, February 07). ZIF-8 Nanofibers Enhance MOF CO2 Capture Capabilities. AZoNano. Retrieved on July 04, 2022 from https://www.azonano.com/news.aspx?newsID=38647.

  • MLA

    Rehan, Shaheer. "ZIF-8 Nanofibers Enhance MOF CO2 Capture Capabilities". AZoNano. 04 July 2022. <https://www.azonano.com/news.aspx?newsID=38647>.

  • Chicago

    Rehan, Shaheer. "ZIF-8 Nanofibers Enhance MOF CO2 Capture Capabilities". AZoNano. https://www.azonano.com/news.aspx?newsID=38647. (accessed July 04, 2022).

  • Harvard

    Rehan, Shaheer. 2022. ZIF-8 Nanofibers Enhance MOF CO2 Capture Capabilities. AZoNano, viewed 04 July 2022, https://www.azonano.com/news.aspx?newsID=38647.

Tell Us What You Think

Do you have a review, update or anything you would like to add to this news story?

Leave your feedback
Your comment type
Submit