Paper-Like Writable Nanoparticle Network Sheets for Mask-Less MOF Patterning

Geometrical structuring of monolithic metal-organic frameworks (MOFs) components is required for their practical implementation in many areas, including electronic devices, gas storage/separation, catalysis, energy storage as well as bio-medical applications. Despite progress in structuring MOFs, an approach for the precise patterning of MOF functional geometries in the millimeter- to micro-meter depth is lacking. Here, a facile and flexible concept for the microfabrication of complex MOF patterns on large surfaces is reported. The method relies on the engineering of easily-writable sheets of precursor metal oxide nanoparticles. The gas-phase conversion of these patterned ceramic nanoparticle sheets results in monolithic MOF objects with arbitrarily shaped geometries and thicknesses of up to hundreds of micrometers. The writing of complex patterns of zeolitic imidazolate framework-8 (ZIF-8) is demonstrated by a variety of approaches including ion beam, laser, and hand writing. Nanometer-scale patterns are achieved by focused ion beam (FIB). Artless handwritings are obtained by using a pen in a similar fashion to writing on a paper. The pure ZIF-8 composition of the resulting patterns is confirmed by a series of physical and chemical characterization. This facile MOF precursor-writing approach provides novel opportunities for the design of MOF-based devices with applications ranging from micro-fluidics to renewable energy systems.