Prof. Wen-Jun WANG's Group

Deposition of Metal-Organic Framework Thin Films on Polymer Fibers for Adsorptive Functional Materials

Junjie Zhao

North Carolina State University

Metal-organic frameworks (MOFs) are porous, crystalline materials consisting of metal-containing units and organic bridging ligands. With ultra-high surface area, large pore volume and availability for post-synthetic modification, MOFs are good candidates for gas adsorption and storage. However, MOF powders require further manipulation and handling, and may not be the ideal configuration for applications such as filtration, separation and sensing. Integration of MOF thin films on polymeric fibrous scaffolds can simplify deployment and broaden the applications.

Conventional synthesis methods are difficult to adapt to polymer substrates, and generally lead to poor growth uniformity, low mass uptake and limited accessible surface area. We discovered a conformal metal oxide thin film via atomic layer deposition (ALD) can dramatically improve MOF heterogeneous nucleation on fibers for both solvothermal and layer-by-layer methods. These MOF-functionalized fiber materials are readily handled and could be easily installed into a variety of technological systems. For hazardous gas removal, for example, our materials exhibit ultra-high NH₃ and H₂S adsorption capacity. Moreover, our process scheme is generally applicable to a wide range of polymer fibers and MOFs, representing a new technological platform that will expand the application set for MOF materials.