MOF‐on‐MOF: Oriented Growth of Multiple Layered Thin Films of Metal–Organic Frameworks

Abstract

The precise alignment of multiple layers of metal–organic framework (MOF) thin films, or MOF‐on‐MOF films, over macroscopic length scales is presented. The MOF‐on‐MOF films are fabricated by epitaxially matching the interface. The first MOF layer (Cu2(BPDC)2, BPDC=biphenyl‐4,4′‐dicarboxylate) is grown on an oriented Cu(OH)2 film by a “one‐pot” approach. Aligned second (Cu2(BDC)2, BDC=benzene 1,4‐dicarboxylate, or Cu2(BPYDC)2, BPYDC=2,2′‐bipyridine‐5,5′‐dicarboxylate) MOF layers can be deposited using liquid‐phase epitaxy. The co‐orientation of the MOF films is confirmed by X‐ray diffraction. Importantly, our strategy allows for the synthesis of aligned MOF films, for example, Cu2(BPYDC)2, that cannot be grown on a Cu(OH)2 surface. We show that aligned MOF films furnished with Ag nanoparticles show a unique anisotropic plasmon resonance. Our MOF‐on‐MOF approach expands the chemistry of heteroepitaxially oriented MOF films and provides a new toolbox for multifunctional porous coatings.

Atomic/Molecular Layer Deposited Iron–Azobenzene Framework Thin Films for Stimuli‐Induced Gas Molecule Capture/Release

“…Crystalline metal-organic networks such as the so-called coordination polymer (CP) and metal-organic framework (MOF) materials, [1][2][3] are intensively investigated for av ast arena of advanced applications,inparticular those related to gas or drug molecule capture,storage,and delivery. [4][5][6][7] As an exciting option to widen the application horizon, adding ar emote-controlled functionality could be imagined by introducing astimuli-responsive component within the framework structure.P hotostimulation is an attractive choice as light is au biquitous and sustainable resource,a nd moreover offers high spatial and temporal resolution.…”

Atomic/Molecular Layer Deposited Iron–Azobenzene Framework Thin Films for Stimuli‐Induced Gas Molecule Capture/Release

“…Crystalline metal–organic networks such as the so‐called coordination polymer (CP) and metal–organic framework (MOF) materials, are intensively investigated for a vast arena of advanced applications, in particular those related to gas or drug molecule capture, storage, and delivery . As an exciting option to widen the application horizon, adding a remote‐controlled functionality could be imagined by introducing a stimuli‐responsive component within the framework structure.…”

Unveiling the mechanism of lattice-mismatched crystal growth of a core–shell metal–organic framework

“…One class of the latter that is still somewhat rare, but accesses additional levels of structural and functional diversity, is core-shell latticemismatched MOFs (CS-LM-MOFs) in which the shell MOF has a different framework composition and unit cell from the underlying core MOF to which it is directly connected. [11][12][13][14][15][16][17][18] Currently, information is known concerning the crystal morphology and composition of these CS-LM-MOFs, and the diffraction details of the shell MOF and its crystallographic orientation relative to the core. [11][12][13][14][15][16][17] However, little is known concerning the actual nanoscale growth mechanism of the lattice-mismatched shell MOF over the core MOF, and the inuence on the crystal form of the shell MOF resulting from such mismatch.…”

“…[11][12][13][14][15][16][17][18] Currently, information is known concerning the crystal morphology and composition of these CS-LM-MOFs, and the diffraction details of the shell MOF and its crystallographic orientation relative to the core. [11][12][13][14][15][16][17] However, little is known concerning the actual nanoscale growth mechanism of the lattice-mismatched shell MOF over the core MOF, and the inuence on the crystal form of the shell MOF resulting from such mismatch. Such a dearth of knowledge is surprising given that the exciting properties and functionalities of CS-LM-MOFs, such as size selective catalysis 14 and orientation dependent plasmon resonance, 15 may critically depend on the overall form of the MOF shell, the defects it contains and its interfacial structure with the core MOF.…”

“…[11][12][13][14][15][16][17] However, little is known concerning the actual nanoscale growth mechanism of the lattice-mismatched shell MOF over the core MOF, and the inuence on the crystal form of the shell MOF resulting from such mismatch. Such a dearth of knowledge is surprising given that the exciting properties and functionalities of CS-LM-MOFs, such as size selective catalysis 14 and orientation dependent plasmon resonance, 15 may critically depend on the overall form of the MOF shell, the defects it contains and its interfacial structure with the core MOF. In situ atomic force microscopy (AFM), 18,19 and the synthesis components and conditions of MOF crystallisation 20 form an ideal combination for lling this knowledge void [21][22][23][24][25][26][27][28] and providing unprecedented understanding of the formation of CS-LM-MOFs, and latticemismatched core-shell materials in general.…”