Metal-organic frameworks (MOFs) are a class of porous crystalline materials featuring high surface area, ordered pore structures and amenability for post-synthetic modification. Integrating MOF thin films with various substrate materials could enable applications in separations, heterogeneous catalysis, chemical sensors and electronic devices. However, it is difficult to find a universal approach to deposit uniform and high-quality MOF coatings on a variety of substrate materials. Previous attempts often require surface modification methods that may not be generally applicable.

In this talk, interfacial engineering using atomic layer deposited (ALD) templates will be discussed for forming MOF thin films on various substrates. We found that ALD metal oxides are effective in promoting the heterogeneous nucleation of MOFs and also readily hydrolyzed into hydroxy double salts (HDSs) for rapid transformation to MOFs. With ALD template layers, conformal and functional MOF coatings were integrated on fibers, membranes and laminated structures. Accordingly, we developed a series of MOF-functionalized fibers for adsorption and catalytic degradation of hazardous compounds. Furthermore, we obtained ultra-thin mixed-metal MOF skin layers on porous alumina supports for membrane separation, and achieved large propylene permeance (up to 4.5×10^-8 mol·m^-2·s^-1·Pa^-1) and high propylene/propane selectivity over 250. We anticipate that this platform technology will also lead to potential device structures for chemical sensing, energy storage and many other scenarios.