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The application of conventional metal–organic frameworks (MOFs) as electrode materials in supercapacitors is largely hindered by their conventionally poor electrical conductivity. This study reports the fabrication of conductive MOF nanowire arrays (NWAs) and the application of them as the sole electrode material for solid‐state supercapacitors. By taking advantage of the nanostructure and making full use of the high porosity and excellent conductivity, the MOF NWAs in solid‐state supercapacitor show the highest areal capacitance and best rate performance of all reported MOF materials for supercapacitors, which is even comparable to most carbon materials.

Recently, the emergence of conductive metal-organic frameworks (MOFs) has given great prospects for their applications as active materials in electronic devices. In this work, a high-quality, free-standing conductive MOF membrane was prepared by an air-liquid interfacial growth method. Accordingly, field-effect transistors (FETs) possessing a crystalline microporous MOF channel layer were successfully fabricated for the first time. The porous FETs exhibited p-type behavior, distinguishable on/off ratios, and excellent field-effect hole mobilities as high as 48.6 cm V s, which is even comparable to the highest value reported for solution-processed organic or inorganic FETs.

The utility of electronically conductive metal-organic frameworks (EC-MOFs) in high-performance devices has been limited to date by a lack of high-quality thin film. The controllable thin-film fabrication of an EC-MOF, Cu (HHTP) , (HHTP=2,3,6,7,10,11-hexahydroxytriphenylene), by a spray layer-by-layer liquid-phase epitaxial method is reported. The Cu (HHTP) thin film can not only be precisely prepared with thickness increment of about 2 nm per growing cycle, but also shows a smooth surface, good crystallinity, and high orientation. The chemiresistor gas sensor based on this high-quality thin film is one of the best room-temperature sensors for NH among all reported sensors based on various materials.

A strategy for combining metal oxides and metal-organic frameworks is proposed to design new materials for sensing volatile organic compounds, for the first time. The prepared ZnO@ZIF-CoZn core-sheath nanowire arrays show greatly enhanced performance not only on its selectivity but also on its response, recovery behavior, and working temperature.

The preparation of crystalline, ordered thin films of metal-organic frameworks (MOFs) will be a critical process for MOF-based nanodevices in the future. MOF thin films with perfect orientation and excellent crystallinity were formed with novel nanosheet-structured components, Cu-TCPP [TCPP = 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin], by a new "modular assembly" strategy. The modular assembly process involves two steps: a "modularization" step is used to synthesize highly crystalline "modules" with a nanosized structure that can be conveniently assembled into a thin film in the following "assembly" step. With this method, MOF thin films can easily be set up on different substrates at very high speed with controllable thickness. This new approach also enabled us to prepare highly oriented crystalline thin films of MOFs that cannot be prepared in thin-film form by traditional techniques.

The electrical properties of a highly oriented crystalline MOF nanofilm were studied. This nanofilm has low activation energy and a proton conductivity that is among the highest value reported for MOF materials. The study uncovered the reasons for the excellent performance of this nanofilm and revealed a new pathway for proton transport in MOF materials; besides the channels inside a MOF, the surface of the MOF nanocrystal can also dominate proton transport.

The distinct synergetic characteristics between each component in inorganic-organic hybrids offer various possibilities to obtain new "smart", high performing materials. Growing interest in this field has largely expanded the content of photochromic materials for the purpose of improving existing photochromic materials, fabricating photoresponsive devices, and exploring new families of photochromic materials. In this feature article, we give a brief review of photochromic hybrids of metal halides, metal cyanides, polyoxometalates, and metal chalcogenides as well as photochromic metal-organic complexes.