2025 AIChE Annual Meeting

(286c) Fabrication of Piezoelectric Polymer-MOF Composite Fims Via Solution Shearing

Authors

Ankit Dhakal - Presenter, University of Virginia
Byungjoon Bae, University of Virginia
Shubha Gunaga, Florida State University
Amrit Venkatesh, University of Virginia
Gaurav Giri, University of Virginia
Integrating polymers with metal-organic frameworks (MOFs) to form polymer-MOF composites has emerged as a promising strategy to improve MOFs processibility and applicability. Furthermore, thin films of polymer-MOF composites are particularly attractive for applications in flexible electronics, sensors, and separation technologies. However, conventional MOF film fabrication methods such as layer by layer and solvothermal are time intensive and hence difficult to scale up. In this regard, recently a meniscus guided coating technique also known as solution shearing has gained attention for rapidly producing large-area MOF-based films.

In this study, UiO-66 (a zirconium-based MOF) was first synthesized in situ in the presence of a piezoelectric polymer poly (vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)]. The resulting composite was then processed into a thin film using the solution shearing technique. We explored how varying the polymer content during synthesis affects film characteristics, including crystallinity, surface coverage and piezoelectric behavior. Furthermore, we utilized solid state nuclear magnetic resonance (NMR) spectroscopy to probe the interactions between the polymer and the MOF components. Evidence from 2D 13C{1H} HETCOR solid-state NMR spectra with 1H-1H spin diffusion indicated polymer-MOF interactions, suggesting that polymer strands are in close proximity to UiO-66 pores, supporting a mixed surface coating and pore infiltration model. Additionally, the incorporation of P(VDF-TrFE) significantly improved the films areal coverage and piezoelectric output. The composite film containing 91 wt. % P(VDF-TrFE) showed the highest piezoelectric performance, generating an output voltage of 9.1 V under mechanical stress. These results demonstrate that solution shearing is a viable and scalable technique for fabricating high-performance polymer-MOF films.