王文俊课题组

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.

 

金属-有机框架材料(MOF)薄膜在高分子纤维表面的生长方法及吸附应用

赵俊杰

北卡罗来纳州立大学

金属-有机框架材料(MOF)是一类多孔晶体材料，由金属结点和有机配体组成，常具有超大比表面积、高孔隙率和可修饰性等特性，可以被用作吸附剂。由于传统的溶剂热法制备的MOF呈粉末状且不溶于常见溶剂，它在气体净化、分离、检测方面的应用受到限制。将MOF与高分子纤维结合能够使其更易于使用，并能拓展其用途。

传统的MOF制备方法很难直接用于高分子基底材料，因为这些方法制得的MOF在基底材料上的均一性较差，生长率较低，且有效比表面积较小。我们通过研究发现，在纤维表面用原子层沉积(ALD)的方法生长一层纳米级金属氧化物薄膜，可以用作MOF非均相生长的晶种层。通过这种晶种层，溶剂热法和逐层生长的方法都能获得良好的均一性、高生长率和大比表面积。所制备的功能材料易于使用、用途广泛。在有害气体吸附方面，这种以纤维为基底的MOF材料表现出极高的氨气、硫化氢吸附能力。此外，我们的制备方法可广泛应用于多种高分子纤维以及不同类型的MOF材料，使得MOF材料的进一步应用成为可能。