Freestanding MOF Microsheets with Defined Size and Geometry Using Superhydrophobic–Superhydrophilic Arrays

Abstract

Metal-Organic Frameworks (MOF) formed by self-assembly of organic ligands and metal ions have emerged as an important class of porous crystalline materials.[1] Arising from their high variability in the choice of organic ligands and metal centers, suitable for the MOF synthesis, a large number of crystal structures have been developed making them attractive candidates for various applications such as gas storage, [2] separation, [3] [4] catalysis, [5] sensing, [6] electronics [7] and drug delivery. [8] Next to the design of new crystal structures and incorporation of novel functional groups recently larger attention has also been drawn to the structuring of MOFs at the mesoscopic/macroscopic scale [2] as well as their positioning.[9] The possibility of incorporating MOF crystals inside superstructures combined with precise positioning will play an important role towards improving their performance and incorporating them into functional devices.

Micro‐/Nanostructured Interface for Liquid Manipulation and Its Applications

“…2) The position, geometry, amount and size of the (micro)reservoir could be precisely adjusted and organized by intelligent and flexible design of the (super)wettability patterns (Figure b). For example, the volume of microdroplet had been reported to be as low as picoliter and femtoliter, and the geometry of the (micro)reservoir can be tuned for the synthesis of materials with specific shapes, such as hydrogel particles, biofilm microcluster, metal organic framework microsheet, and nanoparticle assembly . 3) (Micro)reservoirs can be spatially close to each other because droplet coalesce is avoided, which paves the way for miniaturization and point‐of‐care application of the SPW .…”

Droplet Microarrays: From Surface Patterning to High‐Throughput Applications

“…Recently, our group demonstrated an interfacial synthesis of freestanding metal-organic framework (MOF) microsheets, HKUST-1(Cu 3 btc 2 ), with defined size and geometry on superhydrophobic-superhydrophilic patterned surfaces ( Figure 9A). [110] This was achieved by first creating an array of copper acetate aqueous microdroplets with defined geometries via discontinuous dewetting, followed by covering the droplet microarrays with a waterimmiscible solution of benzene tricarboxylic acid in 1-octanol. The nucleation and growth of MOFs occurred only at the water-octanol interface, thereby leading to MOF microsheets with geometries defined by that of the wateroctanol interface.…”

Immobilization of Water Drops on Hydrophobic Surfaces by Contact Line Pinning at Nonlithographically Generated Polymer Microfiber Rings

“…Discrete water drops immobilized on substrates have been explored for a diverse range of applications including the trapping of bioactive molecules, nonadherent cells, and microorganisms . Moreover, immobilized water drops were employed for enzymatic reactions, synthesis and profiling of enzyme inhibitors, combinatorial discovery of fluorescent pharmacophores, high‐throughput screenings of embryonic stem cells, whole‐organism screenings using fish embryos, as well as for the creation of cell type patterns, microdrop‐derived hydrogel particles and metal‐organic framework (MOF) microstructures . The most common and viable strategy to immobilize water drops is the use of hydrophobic–hydrophilic micropatterns—the water drops are located on hydrophilic areas bordered by hydrophobic areas.…”