Liquid-phase epitaxy of metal organic framework thin films

Abstract

Metal-organic framework (MOF) thin films are multilayer materials ranging from nanometers to micrometers in thickness, physically or chemically adhesive to a (functionalized) substrate and, in an ideal case, exhibiting low roughness and high homogeneity. Various innovative approaches have been developed for MOF thin film fabrication. Among these advanced materials, surface-attached metal-organic frameworks (SURMOFs) are an important class of MOF films. SURMOFs, fabricated in a step-by-step liquid phase epitaxial (LPE) fashion by alternating deposition of metal and organic linker precursors on a functionalized substrate, for example, thiolate-based self-assembled monolayers (SAMs), have already exhibited their utility in both research and potential applications. SURMOFs combine surface science and the chemistry of MOFs, possessing the following unique advantages that cannot be accessed through other methods: (i) precisely controlling thickness, roughness and homogeneity as well as growth orientation, (ii) studying of MOF growth mechanism, (iii) modifying/tailoring MOFs' structures during the SURMOF growth and thus creating customizable properties, and (iv) existing in the form of thin film/membrane for direct applications, for example, as sensors. This review discusses the oriented and crystalline SURMOFs fabricated by LPE approach, covering their preparation, growth mechanism, and characterization methodology as well as applications based upon the most newly updated knowledge. coordination chemistry, metal-organic frameworks (MOFs), liquid phase epitaxy, step-by-step approach, surface science, thin film

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“…Bo Liu and Roland Fischer discussed the oriented and crystalline SURMOFs fabricated by a step-by-step liquid phase epitaxial (LPE) approach. Their article covers the preparation of SURMOFs, their growth mechanism, characterization methods, and applications [15]. Wuzong Zhou and coworkers discussed recent work in reversed crystal growth mechanism [16].…”

“…The paper by Liu and Fischer summarized the oriented and crystalline SURMOFs and their unusual applications that MOF thin films prepared by other techniques do not have, including their external surface functionalization, hybridized SURMOF with specified modification, and enantioselective adsorption on homochiral SURMOF [15].…”

Mass transport through metal organic framework membranes

“…It is necessary for MOF membranes to be well-intergrown, since the pinholes, grain boundary and cracks can significantly reduce the selectivity. In addition, MOF membranes are generally required to be synthesized on the top of substrates [80][81][82][83], contrast to the free-standing MOF-based MMMs. Thus, the fabrication of MOF membranes needs to be well-designed, although MOF powders can be prepared easily by hydrothermal or solventhermal method.…”

Electrosynthesis of Metal–Organic Frameworks: Challenges and Opportunities

“…The autoclave is then heated to above the boiling point of the solvent at elevated pressures for ac ertain number of hours, or even days, to allow the formation of the desired MOF.S olvothermals yntheses are carriedo ut at lower temperatures and atmospheric pressure to allow diffusion-controlled synthesis with promise for applications in crystal engineering. [34] Other methods include microwave-assisted, [35] mechanochemical, [36] liquid-phase epitaxy, [37] sonochemical [38] and recently,e lectrochemical techniques. Electrochemical methods have severala dvantages over the others, such as, shorter synthesis times and milder synthesis conditions.…”