ZIF-8 crystal coatings on a polyimide substrate and their catalytic behaviours for the Knoevenagel reaction

Abstract

ZIF-8 crystal coatings were prepared by direct growth on different flexible polyimide substrates including a thin membrane and electrospun nanofiber mat. In SEM pictures, the ZIF-8 crystals exhibit a rhombic dodecahedron morphology. Owing to the flexible polyimide substrate, the MOF-polymer film may be moderately bent or easily tailored when not destroyed. The ZIF-8 coatings can be activated at high temperature owing to the excellent thermal resistance and low coefficient of thermal expansion of the polyimide. Furthermore, this material may be used as an efficient heterogeneous catalyst for the Knoevenagel reaction and can be easily recovered. The ZIF-8 coatings and 2-methylimidazole show similar catalytic behaviour as a weak base.

Rapid fabrication of metal–organic framework thin films using in situ microwave irradiation and its photocatalytic property

“…For a practical use, deposition of MOFs on substrates to fabricate MOFs thin films have attracted much attraction due to their potential applications in catalysis, sensors, and gas separations [8][9][10].…”

“…MOFs have drawn considerable attention in recent years owing to fine tune size, shape, and chemical functionality of the cavities and the internal surfaces by changing the organic liker groups [1][2][3].With such exceptional properties, MOFs have great potential in diverse applications such as catalysis, drug delivery, gas _________________________________ ACCEPTED MANUSCRIPT 2 adsorption, magnetic imaging and sensing [4][5][6][7]. For a practical use, deposition of MOFs on substrates to fabricate MOFs thin films have attracted much attraction due to their potential applications in catalysis, sensors, and gas separations [8][9][10].Recently, several synthesis schemes have been developed for the fabrication of MOFs thin film on different solid substrates, such as silica, porous alumina, graphite and gold surfaces [11][12]. Diverse synthesis approaches for MOFs thin films and membranes have been employed, and can be classified into two approaches: One is in situ or by secondary growth after seeding from a supporting membrane, and the other is to incorporate pre-synthesized MOFs into matrix materials to form mixed-matrix membranes (MMMs) [13].…”

“…MOFs have drawn considerable attention in recent years owing to fine tune size, shape, and chemical functionality of the cavities and the internal surfaces by changing the organic liker groups [1][2][3].With such exceptional properties, MOFs have great potential in diverse applications such as catalysis, drug delivery, gas _________________________________ ACCEPTED MANUSCRIPT 2 adsorption, magnetic imaging and sensing [4][5][6][7]. For a practical use, deposition of MOFs on substrates to fabricate MOFs thin films have attracted much attraction due to their potential applications in catalysis, sensors, and gas separations [8][9][10].…”

Metal‐Organic Frameworks: Coordination Polymer Nanoparticles and Macrostructures

“…12-14 Three-dimensional PCPbased architectures possessing a multimodal porosity are useful to improve the molecular diffusion when used as separation systems and catalysts. 15,16 Owing to the highly reactive surfaces of PCPs (composed of partially coordinated organic ligands or uncoordinated metal centers), the possible modulation of the coordination equilibrium, and the large number of PCP framework available (implying a large range of possible synthesis conditions), many of the chemical and microfabrication methods established for the manipulation of both purely organic and inorganic compounds were applied for the synthesis of PCPs. As it will be illustrated later in this chapter, utilization of microwave treatment, microemulsion methods, or capping agents was successful for the control of the size and shape of PCP crystals.…”

Layer-by-layer decoration of MOFs on electrospun nanofibers

“…The second strategy is the in situ growth of MOFs on the electrospun nanobers. 8,[41][42][43][44][45][46][47][48][49][50][51][52][53] Peterson and Parsons found that Zr-based MOF thin lms could be formed in situ on the TiO 2 coatings, which was deposited via atomic layer deposition onto polyamide-6 electrospun nanobers. 51 Another work presented by Ma and coworkers showed that bimetal ZIFs could directly grow on 2-methylimidazole/PAN electrospun nanober mats, which showed excellent electrocatalytic performance for oxygen reduction reaction aer the carbonization step.…”