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Many odors, like perfumes, are complex mixtures of chiral and achiral molecules where the cost‐efficient (enantio−)selective sensing represents a major technical challenge. Here, we present a colorimetric sensor array of surface‐mounted metal‐organic‐framework (SURMOF) films in Fabry‐Pérot (FP) cavities. The optical properties of the FP‐SURMOF films with different chiral and achiral structures are affected by the (enantio−)selective adsorption of the analytes in the SURMOF pores, resulting in different responses to the analyte molecules. The read‐out of the sensor array is performed by the digital camera of a common smartphone, where the RGB values are determined. By analyzing the sensor array data with simple machine learning algorithms, the analytes are discriminated. After demonstrating the enantioselective response for a pair of pure chiral odor molecules, we apply the sensor array to detect and discriminate a large number (16) of common commercial perfumes and eau de toilettes. While our untrained human nose is not able to discriminate all perfumes, the presented colorimetric sensor array can classify all perfumes with great classification accuracy. Moreover, the sensor array was used to identify unlabeled samples correctly. We foresee such an FP‐chiral‐SURMOF‐based sensor array as a powerful approach toward inexpensive selective odors sensing applications. [ABSTRACT FROM AUTHOR]

Many properties of the emerging class of metal‐organic frameworks (MOFs) depend crucially on defect concentrations, as in case of other solids. In order to provide reference systems with nearly perfect structure and low defect density, a procedure to grow MOFs epitaxially on cm‐sized Si(111) single crystals is developed. The crystalline metal‐organic thin films are in high registry with the substrate's crystal lattice, as demonstrated by synchrotron‐based grazing incidence X‐ray diffraction (GI‐XRD) experiments. The corresponding reduction of MOF defect density is shown to have striking effects on the properties of these porous frameworks. The most pronounced difference concerns mass transport. An increase in the diffusion coefficient of guest molecules by one order of magnitude relative to the same MOF materials with normal defect densities is observed. [ABSTRACT FROM AUTHOR]

Electronic circular dichroism is an important optical phenomenon offering insights into chiral molecular materials. On the other hand, metal–organic frameworks (MOFs) are a novel group of crystalline porous thin‐film materials that provide tailor‐made chemical and physical properties by carefully selecting their building units. Combining these two aspects of contemporary material research and integrating chiral molecules into MOFs promises devices with unprecedented functionality. However, considering the nearly unlimited degrees of freedom concerning the choice of materials and the geometrical details of the possibly structured films, urgently it needs to complement advanced experimental methods with equally strong modeling techniques. Most notably, these modeling techniques must cope with the challenge that the material and devices thereof cover size scales from Ångströms to mm. In response to that need, a computational workflow is outlined that seamlessly combines quantum chemical methods to capture the properties of individual molecules with optical simulations to capture the properties of functional devices made from these molecular materials. The focus is on chiral properties and applying work to UiO‐67‐BINOL MOFs, for which experimental results are available to benchmark the results of the simulations and explore the optical properties of cavities and metasurfaces made from that chiral material. [ABSTRACT FROM AUTHOR]

Organic semiconductors, specifically polycyclic aromatic chromophores like pentacene, coronene, and nanographenes (hexa‐peri‐hexabenzocoronene, HBC), are often utilized in optoelectronic applications due to their intriguing single‐molecule properties. However, the integration of these aromatic compounds into optoelectronic devices frequently encounters significant obstacles, primarily due to the unpredictable and challenging control over the structure and morphology of their condensed phase. Rather than resorting to chemical modifications or advanced thin‐film manufacturing methods such as chemical vapor deposition, the so‐called metal‐organic framework (MOF) approach is employed to create a highly photoresponsive, nanographene‐based thin film employing a layer‐by‐layer, liquid‐phase epitaxy method. It is demonstrated that the novel Cu‐HBC MOF thin film exhibits excellent photoresponsive behavior under ultraviolet illumination, including a fast response time (˂ 0.02 s) and high current switching ratio (≈104), which significantly outperforms an isostructural MOF Zn‐HBC. Furthermore, it is demonstrated that the metal nodes inside the MOF can be used to enhance the photoresponse by efficient exciton splitting. [ABSTRACT FROM AUTHOR]

A highly sensitive and low‐power sensing platform for detecting ethanol molecules by interfacing high‐purity, large‐diameter semiconducting carbon nanotube transistors with a metal–organic framework layer is presented. The new devices outperform similar graphene‐based metal–organic framework devices by several orders of magnitude in terms of sensitivity and power consumption, and can detect extremely low ethanol concentrations down to sub‐ppb levels while consuming only picowatts of power. The exceptional sensor performance results from the nanotube transistor's high on/off ratio and its sensitivity to charges, allowing for ultra‐low power consumption. The platform can also compensate for shifts in threshold voltage induced by ambient conditions, making it suitable for use in humid air. This novel concept of MOF/CNTFETs could be customized for detecting various gaseous analytes, leading to a range of ultra‐sensitive and ultra‐low power sensors. [ABSTRACT FROM AUTHOR]

The mass transfer in a film of metal‐organic framework with one‐dimensional pores, oriented perpendicular to the substrate surface, was gravimetrically explored. The diffusion coefficients of the probe molecules cyclohexane and p‐xylene were determined from the transient uptake curves. When exchanging cyclohexane by p‐xylene in the MOF pores, the mass transfer was significantly slower than the plain, single‐component uptakes. However, a single‐file‐diffusion situation, where mutual passage is hindered, tremendously slowing down the mass transfer, was not found. [ABSTRACT FROM AUTHOR]

The unique properties of 2D‐materials like graphene are exploited in various electronic devices. In sensor applications, graphene shows a very high sensitivity, but only a low specificity. This shortcoming can be mastered by using heterostructures, where graphene is combined with materials exhibiting high analyte selectivities. Herein, this study demonstrates the precise deposition of nanoporous metal‐organic frameworks (MOFs) on graphene, yielding bilayers with excellent specificity while the sensitivity remains large. The key for the successful layer‐by‐layer deposition of the MOF films (SURMOFs) is the use of planar polyaromatic anchors. Then, the MOF pores are loaded with ionic liquid (IL). For functioning sensor devices, the IL@MOF films are grown on graphene field‐effect transistors (GFETs). Adding a top‐gate electrode yields an ion‐gated GFET. Analysis of the transistor characteristics reveals a clear Dirac point at low gate voltages, good on‐off ratios, and decent charge mobilities and densities in the graphene channel. The GFET‐sensor reveals a strong and selective response. Compared to other ion‐gated‐FET devices, the IL@MOF material is relatively hard, allowing the manufacturing of ultrathin devices. The new MOF‐anchoring strategy offers a novel approach generally applicable for the functionalization of 2D‐materials, where MOF/2D‐material hetero‐bilayers carry a huge potential for a wide variety of applications. [ABSTRACT FROM AUTHOR]

The unambiguous detection and classification of volatile organic compounds (VOCs) are crucial in many fields. For using VOC‐sensing to explore the alteration and spoilage of food, very inexpensive sensors are desired. Simple colorimetric sensors seem highly attractive for these applications. Here, a label‐free, colorimetric sensor array made of metal‐organic‐framework‐based (MOF‐based) Fabry‐Pérot (FP) films is presented where the signal read‐out is performed either by their optical spectra or by pictures taken with a smartphone camera. Exposing the FP‐MOF‐films to various VOCs causes a reversible shift of the photonic pattern, where the magnitude of the shift depends on the VOC type, its concentration, and the MOF structure. The application of machine‐ learning‐ algorithms on the sensor data allows to identify the VOCs with a high classification accuracy (92% at 100 ppm). It is shown that the sensor array read‐out can also be performed with a common smartphone camera, also precisely classifying the VOC analytes. Moreover, fresh and spoiled food, like milk and meat, is distinguished by its head space. Thus, the study presents a very inexpensive platform of small colorimetric sensors that allow determining the quality, alteration, and spoilage of food, and it may contribute to realizing smart labels and intelligent packaging. [ABSTRACT FROM AUTHOR]

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Molecular machines and responsive materials open a plethora of new opportunities in nanotechnology. We present an oriented crystalline array of diarylethene (DAE)‐based photoactuators, arranged in a way to yield an anisotropic response. The DAE units are assembled, together with a secondary linker, into a monolithic surface‐mounted metal–organic framework (SURMOF) film. By Infrared (IR) and UV/Vis spectroscopy as well as by synchrotron X‐ray diffraction, we show that the light‐induced extension changes of the molecular DAE linkers multiply to yield mesoscopic and anisotropic length changes. Due to the special architecture and substrate‐bonding of the SURMOF, these length changes are transferred to the macroscopic scale, leading to the bending of a cantilever and performing work. This research shows the potential of assembling light‐powered molecules into SURMOFs to yield photoactuators with a directed response, presenting a path to advanced actuators. [ABSTRACT FROM AUTHOR]

For optoelectronic applications of metal–organic framework (MOF) thin films, it is important to be able to fabricate films and heterostructures that are highly oriented relative to the substrate's surface normal. However, process optimization to achieve this is difficult without sufficiently detailed structural characterization of the deposited films. It is demonstrated that 2D grazing‐incidence wide‐angle X‐ray scattering (GIWAXS) data from a laboratory system go a long way to providing such characterization and can 1) better test structural models than 1D scans, 2) provide a quantitative estimate—useful for process optimization—of the fraction of the deposited film that has the desired surface‐oriented texture (2D powder), and 3) deliver such information as a function of depth into the film—useful for heterostructure characterization. Herein, GIWAXS data collection and analysis are introduced in the context of understanding MOF thin films, then it is shown how the desired oriented fraction (2D powder fraction) of UiO‐66 fabricated by vapor‐assisted conversion can be increased from 4% to over 95% by minimizing nucleation in solution. Finally, it is demonstrated that heterostructures of UiO‐66 and UiO‐67 can be grown wherein both layers are highly ordered (UiO‐66 83%, UiO‐67 >94%) once synthetic protocols are optimized. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

While materials based on organic molecules usually have either superior optoelectronic or superior chiral properties, the combination of both is scarce. Here, a crystalline chiroptical film based on porphyrin with homochiral side groups is presented. While the dissolved molecule has a planar, thus, achiral porphyrin core, upon assembly in a metal–organic framework (MOF) film, the porphyrin core is twisted and chiral. The close packing and the crystalline order of the porphyrin cores in the MOF film also results in excellent optoelectronic properties. By exciting the Soret band of porphyrin, efficient photoconduction with a high On‐Off‐ratio is realized. More important, handedness‐dependent circularly‐polarized‐light photoconduction with a dissymmetry factor g of 4.3×10−4 is obtained. We foresee the combination of such assembly‐induced chirality with the rich porphyrin chemistry will enable a plethora of organic materials with exceptional chiral and optoelectronic properties. [ABSTRACT FROM AUTHOR]

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Molecular motors are fascinating nanomachines. However, constructing smart materials from such functional molecules presents a severe challenge in material science. Here, we present a bottom‐up layer‐by‐layer assembly of oriented overcrowded‐alkene molecular motors forming a crystalline metal–organic framework thin film. While all stator parts of the overcrowded‐alkene motors are oriented perpendicular to the substrate, the rotors point into the pores, which are large enough allowing for the light‐induced molecular rotation. Taking advantage of the thin film's transparency, the motor rotation and its activation energy are determined by UV/Vis spectroscopy. As shown by gravimetric uptake experiments, molecular motors in crystalline porous materials are used, for the first time, to control the adsorption and diffusion properties of guest molecules in the pores, here, by switching with light between the (meta‐)stable states. The work demonstrates the potential of designed materials with molecular motors and indicates a path for the future development of smart materials. [ABSTRACT FROM AUTHOR]

This article discusses a colorimetric sensor array that uses metal-organic framework films to detect and classify perfume scents. The sensor system is able to detect chiral odor molecules and discriminate between different commercial perfume scents. The sensor read-out is captured using a smartphone camera and analyzed using a machine-learning algorithm. The research article provides more detailed information on the topic. [Extracted from the article]

The loading with guest molecules is the key feature for most applications of metal–organic frameworks (MOFs). The limited stability of MOFs against environmental factors, like humid air, is often a severe problem which hinders real‐life applications. Here, the stability of four common MOFs, UiO‐66, UiO‐67, HKUST‐1, and ZIF‐8, under long‐term exposure to humid air and under exposure to water vapor is explored. Transient uptake experiments with toluene and other volatile organic compounds as probe molecules are combined with structural investigations via X‐ray diffraction and infrared spectroscopy. In line with previous publications showing the structural stability of ZIF‐8 and UiO‐66, it is found that its uptake properties are not affected by exposure to air. On the other hand, HKUST‐1 shows clear structural decomposition in air and degradation of the uptake properties. Unexpectedly, while the diffraction and spectroscopy data of UiO‐67 do not suggest a corrosion of the structure upon air exposure, the guest‐loading data show a strong decrease of the uptake amount and a deceleration of the uptake rate. Both features strongly indicate the formation of surface barriers for the mass transfer in UiO‐67, like in HKUST‐1. The study underlines the importance of transient uptake experiments for characterizing the stability of MOF materials. [ABSTRACT FROM AUTHOR]

Structurally well‐defined, crystalline organic/organic heterojunctions between C60‐ and anthracene‐based semiconductors are realized via layer‐by‐layer deposition of metal‐organic framework, MOF, thin films. As demonstrated by X‐ray diffraction, perfect epitaxy is achieved by adjusting the lattice constants of the two different MOFs. Deposition of top electrodes allows to fabricate p–n as well as n–p devices. Measurements of the electrical properties reveal the presence of high‐performance diodes, with a current on/off ratio of up to 6 orders of magnitude and an ideality factor close to unity. The crystalline nature of the abrupt organic/organic heterojunction provides the basis for a rational, simulation‐based optimization and tailoring of such organic semiconductor interfaces. [ABSTRACT FROM AUTHOR]

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Chirality is essential in nature and often pivotal for biological information transfer, for example, via odor messenger molecules. While the human nose can distinguish the enantiomers of many chiral odors, the technical realization by an artificial sensor or an electronic nose, e‐nose, remains a challenge. Herein, we present an array of six sensors coated with nanoporous metal–organic framework (MOF) films of different homochiral and achiral structures, working as an enantioselective e‐nose. While the achiral‐MOF‐film sensors show identical responses for both isomers of one chiral odor molecule, the responses of the homochiral MOF films differ for different enantiomers. By machine learning algorithms, the combined array data allow the stereoselective identification of all compounds, here tested for five pairs of chiral odor molecules. We foresee the chiral‐MOF‐e‐nose, able to enantioselectively detect and discriminate chiral odors, to be a powerful approach towards advanced odor sensing. [ABSTRACT FROM AUTHOR]

Several photophysical properties of chromophores depend crucially on intermolecular interactions. Thermally‐activated delayed fluorescence (TADF) is often influenced by close packing of the chromophore assembly. In this context, the metal‐organic framework (MOF) approach has several advantages: it can be used to steer aggregation such that the orientation within aggregated structures can be predicted using rational approaches. We demonstrate this design concept for a DPA‐TPE (diphenylamine‐tetraphenylethylene) chromophore, which is non‐emissive in its solvated state due to vibrational quenching. Turning this DPA‐TPE into a ditopic linker makes it possible to grow oriented MOF thin films exhibiting pronounced green electroluminescence with low onset voltages. Measurements at different temperatures clearly demonstrate the presence of TADF. Finally, this work reports that the layer‐by‐layer process used for MOF thin film deposition allows the integration of the TADF‐DPA‐TPE in a functioning LED device. [ABSTRACT FROM AUTHOR]

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In contrast to catalytically active metal single atoms deposited on oxide nanoparticles, the crystalline nature of metal‐organic frameworks (MOFs) allows for a thorough characterization of reaction mechanisms. Using defect‐free HKUST‐1 MOF thin films, we demonstrate that Cu+/Cu2+ dimer defects, created in a controlled fashion by reducing the pristine Cu2+/Cu2+ pairs of the intact framework, account for the high catalytic activity in low‐temperature CO oxidation. Combining advanced IR spectroscopy and density functional theory we propose a new reaction mechanism where the key intermediate is an uncharged O2 species, weakly bound to Cu+/Cu2+. Our results reveal a complex interplay between electronic and steric effects at defect sites in MOFs and provide important guidelines for tailoring and exploiting the catalytic activity of single metal atom sites. [ABSTRACT FROM AUTHOR]

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Photoconductivity is a characteristic property of semi‐conductors. Herein, we present a photo‐conducting crystalline metal–organic framework (MOF) thin film with an on–off photocurrent ratio of two orders of magnitude. These oriented, surface‐mounted MOF thin films (SURMOFs), contain porphyrin in the framework backbone and C60 guests, loaded in the pores using a layer‐by‐layer process. By comparison with results obtained for reference MOF structures and based on DFT calculations, we conclude that donor–acceptor interactions between the porphyrin of the host MOF and the C60 guests give rise to a rapid charge separation. Subsequently, holes and electrons are transported through separate channels formed by porphyrin and by C60, respectively. The ability to tune the properties and energy levels of the porphyrin and fullerene, along with the controlled organization of donor–acceptor pairs in this regular framework offers potential to increase the photoconduction on–off ratio. [ABSTRACT FROM AUTHOR]

Conductive metal–organic frameworks (MOFs) as well as smart, stimuli‐responsive MOF materials have attracted considerable attention with respect to advanced applications in energy harvesting and storage as well as in signal processing. Here, the conductance of MOF films of type UiO‐67 with embedded photoswitchable nitro‐substituted spiropyrans was investigated. Under UV irradiation, the spiropyran (SP) reversibly isomerizes to the open merocyanine (MC) form, a zwitterionic molecule with an extended conjugated π‐system. The light‐induced SP–MC isomerization allows for remote control over the conductance of the SP@UiO‐67 MOF film, and the conductance can be increased by one order of magnitude. This research has the potential to contribute to the development of a new generation of photoelectronic devices based on smart hybrid materials. Photoswitching: Metal–organic framework films were loaded with spiropyran, which photoisomerizes under UV light irradiation to the merocyanine form with a larger conjugated electron system. This isomerization results in a remote‐controlled reversible modification of the material conductance by one order of magnitude. [ABSTRACT FROM AUTHOR]

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Abstract: Metal‐organic frameworks (MOFs) are nanoporous, crystalline hybrid materials, which enable various functionalities by incorporating functional organic molecules. By using organic linker molecules that possess photoswitchable azobenzene side groups, the remote control over certain properties was introduced to MOFs. Different MOF materials in the form of powders and thin films have been used to demonstrate the photoswitching. The applications of these stimuli‐responsive nanoporous solids range from switching the adsorption capacity of various gases over remote‐controlled release of guest molecules to continuously tunable membrane separation of molecular mixtures. A particular focus of this review is the effect of the azobenzene photoswitching on the host‐guest interaction, enabling smart applications of the material. Steric hindrance, which may suppress the photoswitching in some MOF structures, is also discussed. [ABSTRACT FROM AUTHOR]

Stimuli-responsive molecules change their properties when exposed to external signals, such as light, and enable the preparation of smart materials. UV light, which often destroys organic materials, is typically required for activating the desired response of photoswitchable compounds, significantly limiting the potential applications of light-operated smart materials. Herein, we present the first metal-organic framework (MOF), which enables reversible modulation of key properties upon irradiation with visible light only. The fluorinated azobenzene side groups in the MOF structure can be reversibly switched between the trans and cis state by green and violet light, avoiding UV light. It was demonstrated that the uptake of guest molecules by these MOF films can be switched in a fully remote-controlled way. The membrane separation of hydrogen/hydrocarbon mixtures was investigated. The light-induced changes of the MOF pore size result in the switching of the permeation and of the selection factor. [ABSTRACT FROM AUTHOR]

Despite their huge potential for efficient molecular separation, the fabrication of membranes from metal-organic frameworks (MOFs) remains a major challenge. The powders obtained by the conventional solvothermal MOF syntheses are difficult to process, and as a result the fabrication of well-performing, large-area MOF-based membranes is still awaiting success. The deposition of MOF thin films suited for membrane applications is demonstrated by employing a step-by-step spray method. This method can be scaled up to obtain industrially relevant membrane areas and a continuous process is also possible. The performance of sprayed HKUST-1-based membranes by the separation of a binary H2/CO2 mixture is also demonstrated. Furthermore, this approach enables the control of the MOF film thickness, and thus controlling the permeance and the selectivity of the membrane. [ABSTRACT FROM AUTHOR]

While the porphyrin molecules in solution (red) are planar, as common porphyrin, the porphyrin cores are twisted and chiral upon assembly in the metal-organic framework. Keywords: BINOL; Chirales Porphyrin; Fotodetektoren; Metallorganische Gerüste; Zirkular Polarisiertes Licht DE BINOL Chirales Porphyrin Fotodetektoren Metallorganische Gerüste Zirkular Polarisiertes Licht 1 1 1 02/22/23 20230301 NES 230301 B A chiral metal-organic framework film b with optoelectronic properties based on functionalized porphyrin molecules is presented by Mariana Kozlowska, Lars Heinke et al. in their Research Article (e202217377). The close packing and the crystalline order of the porphyrin cores in the film result in excellent photoconduction properties and sensitivity to circularly polarized light. [Extracted from the article]

Inside Back Cover: Twisting of Porphyrin by Assembly in a Metal-Organic Framework yielding Chiral Photoconducting Films for Circularly-Polarized-Light Detection (Angew. BINOL, Chiral Porphyrin, Circularly Polarized Light, Metal-Organic Frameworks, Photodetectors While the porphyrin molecules in solution (red) are planar, as common porphyrin, the porphyrin cores are twisted and chiral upon assembly in the metal-organic framework. [Extracted from the article]

Keywords: Adsorption; Diffusion; Fotoschalter; Metallorganisches Gerüst; Synthetische Molekulare Motoren DE Adsorption Diffusion Fotoschalter Metallorganisches Gerüst Synthetische Molekulare Motoren 1 1 1 01/11/23 20230116 NES 230116 B Photochromic Materials b . In their Communication (e202214202), Lars Heinke et al. report nanoporous films with oriented arrays of molecular motors for light-controlled adsorption and diffusion. [Extracted from the article]

Diffusion, Metal-Organic Framework, Overcrowded Alkene, Photoswitches, Uptake Keywords: Diffusion; Metal-Organic Framework; Overcrowded Alkene; Photoswitches; Uptake EN Diffusion Metal-Organic Framework Overcrowded Alkene Photoswitches Uptake 1 1 1 01/11/23 20230116 NES 230116 B Photochromic Materials b . [Extracted from the article]

The virtually unlimited versatility and unparalleled level of control in the design of metal-organic frameworks (MOFs) has recently been shown to also entail a potential for applications based on the electrical and electronic properties of this rich class of materials. At present, methods to provide reliable and reproducible contacts to MOF materials are scarce; therefore, we have carried out a detailed, multi-technique investigation of an empty and loaded prototype MOF, HKUST-1. Epitaxial thin films of this material grown on a substrate by using liquid-phase epitaxy have been studied by cyclic voltammetry, atomic force microscopy, and quartz crystal microbalance and their quality assessed. By using an ionic liquid as the electrolyte, it is shown that redox-active molecules like ferrocene can be embedded in the pores, enabling a change in the overall conductivity of the framework and the study of the redox chemistry of guest molecules inside the MOF. [ABSTRACT FROM AUTHOR]

Diffusion in nanoporous host–guest systems is often considered to be too complicated to comply with such “simple” relationships as Fick's first and second law of diffusion. However, it is shown herein that the microscopic techniques of diffusion measurement, notably the pulsed field gradient (PFG) technique of NMR spectroscopy and microimaging by interference microscopy (IFM) and IR microscopy (IRM), provide direct experimental evidence of the applicability of Fick's laws to such systems. This remains true in many situations, even when the detailed mechanism is complex. The limitations of the diffusion model are also discussed with reference to the extensive literature on this subject. [ABSTRACT FROM AUTHOR]

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Abstract: Metal–organic frameworks, MOFs, are a class of crystalline porous metal–organic hybrid materials which have originally been developed for applications in gas storage and separation. Here, we demonstrate that due to the enormous chemical flexibility of these molecular materials, they also provide an excellent basis for the development of photoresist materials. In particular, we used an epitaxial process with automated systems to grow either homogeneous or patterned SURMOFs (surface‐anchored MOFs) of the type [Zn2(N3BPDC)2(Dabco)] on different solid substrates. The huge flexibility of the MOF chemistry allowed for different variants of photolithography based on the post‐synthesis modification (PSM) of the MOF materials. Here, two particular and popular PSM‐strategies were employed, the azide–alkyne click reaction and thiol–yne click chemistry. The azide–alkyne click reaction was initiated by the photoreduction of CuII to the active CuI catalyst, whereas the thiol–yne click chemistry was induced directly by UV light. Furthermore, heteroepitaxial growth of multilayer systems (Cu‐N3BPDC+Cu‐BPDC+Cu‐N3BPDC+Cu‐BPDC+Cu‐N3BPDC+Cu‐BPDC) was also used to control the localization of subsequent PSM. The results demonstrated that the patterned functionalization of MOF thin film is not limited to the two dimensions of the mounting surface but is indeed possible in 3D. [ABSTRACT FROM AUTHOR]

Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)