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The pursuit of sustainable, carbon‐free separation technology hinges on the efficient separation of gas mixtures with high separation factors and flow rates, i. e. high permselectivity. However, achieving this objective is arduous due to the meticulous engineering at the angstrom scale and intricate chemical manipulation required to design the pores within membranes. To address this challenge, a proof‐of‐concept for an anisotropic porous membrane has been devised. Employing a meticulous step‐by‐step methodology, two distinct porous metal‐organic frameworks (MOFs) are integrated to form a monolithic anisotropic membrane. By harnessing pore anisotropy (3.4 to 6 Å) aligned with the gas permeation direction and a unique interface characterized by cross‐linked pores derived from the two distinct MOFs, this membrane transcends the performance limitations inherent in the individual MOF membranes (~45 % enhanced selectivity). This approach not only sheds light on the heterolayer membrane design strategy but also elucidates the intricate CO2/N2 permselectivity relationship inherent in the interface structure. [ABSTRACT FROM AUTHOR]

In photo‐induced charge separation, organic thin films with donor and acceptor chromophores are vital for uses such as artificial photosynthesis and photodetection. The main challenges include optimizing charge separation efficiency and identifying the ideal acceptor/donor ratio. Achieving this is difficult due to the variability in molecular configurations within these typically amorphous organic aggregates. Metal–organic frameworks (MOFs) provide a structured solution by enabling systematic design of donor/acceptor blends with adjustable ratios within a crystalline lattice. We demonstrate this approach by incorporating donor and acceptor naphthalenediimide (NDI) chromophores as linkers in a highly oriented, monolithic MOF thin film. By adjusting the NDI acceptor linker concentration during the layer‐by‐layer assembly of surface‐anchored MOF thin films (SURMOFs), we significantly enhanced charge separation efficiency. Surprisingly, the optimum acceptor concentration was only 3 %, achieving a forty‐fold increase in photodetection efficiency compared to baseline NDI donor‐based SURMOFs. This unexpected behaviour was clarified through theoretical analysis enabled by the well‐defined crystalline structure of the SURMOFs. Using density functional theory and kinetic Monte Carlo simulations, we identified two opposing effects from acceptors: the positive effect of suppressing undesirable charge carrier recombination is offset at high concentrations by a reduction in charge‐carrier mobility. [ABSTRACT FROM AUTHOR]

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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]

Performing gas separation at high efficiency with minimum energy input and reduced carbon footprint is a major challenge. While several separation methods exist at various technology readiness levels, porous membrane-based separation is considered as a disruptive technology. To attain sustainability and required efficiency, different approaches of membrane design have been explored. However, the selectivity-permeation trade-off and membrane aging have restricted further advancement. In this regard, a new generation composite made of organic polymers and metal–organic framework (MOF) fillers shows substantial promise. Organic polymer matrix allows easy processibility, but it has poor permselectivity for gas molecules. Metal–organic frameworks are excellent sieving materials; however, they suffer from poor processibility issues. A combination of these two components makes an ideal sieving membrane, which can potentially outnumber the existing energy intensive distillation strategies. In this perspective, we have discussed key indices that regulate gas permselectivity by a careful selection of the existing literature. While the target gas flux and selectivity values have been a part of many previous reviews and articles, we have presented a concise discussion on the interface design of the MOF-polymer membrane, morphology, and orientation control of MOF fillers in the matrix. Following this, a future roadmap to overcome challenges related to MOF-polymer interfacial defects is outlined. [ABSTRACT FROM AUTHOR]

Five isostructural 1D porous coordination polymers (PCPs) with a general formula of {[M(L)(DMF)(H2O)]·1.5H2O}n [M = TbIII (1), EuIII (2), YbIII (3), NdIII (4) and ErIII (5)] have been synthesized using a flexible tripodal organic linker (L) and characterized. TbIII (1) and EuIII (2) PCPs exhibit metal-based green and red emission, respectively, whereas YbIII (3), NdIII (4) and ErIII (5) PCPs show near-infrared (NIR) emission. Doping EuIII in 1 in a precisely controlled stoichiometric amount leads to different mixed lanthanide PCPs, {[Tb1−xEux(L)(DMF)(H2O)]·1.5H2O}n (1a–1f) that show tunable emission including that of bright white light. The PCPs decorated with Lewis basic –O– binding sites make them potential candidates for the binding and selective sensing of traces of CuII ions, and this is illustrated for PCP 2 (limit of detection = 0.69 ± 0.02 ppm). The photoluminescence of 2 can be recovered by the introduction of a chelating ligand ethylenediaminetetraacetic acid (EDTA) without any structural disintegration, indicating the potential of the lanthanide PCPs for future sensing applications. [ABSTRACT FROM AUTHOR]