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Oligoarenes as an alternative group of promising semiconductors in organic optoelectronics have attracted much attention. However, high‐performance and low‐cost opto‐electrical devices based on linear asymmetric oligoarenes with nano/microstructures are still rarely studied because of difficulties both in synthesis and high‐quality nano/microstructure growth. Here, a novel linear asymmetric oligoarene 6‐methyl‐anthra[2,3‐b]benzo[d]thiophene (Me‐ABT) is synthesized and its high‐quality microribbons are grown by a solution process. The solution of Me‐ABT exhibits a moderate fluorescence quantum yield of 0.34, while the microribbons show a glaucous light emission. Phototransistors based on an individual Me‐ABT microribbon prepared by a solution‐phase self‐assembly process showed a high mobility of 1.66 cm2 V−1 s−1, a large photoresponsivity of 12 000 A W−1, and a photocurrent/dark‐current ratio of 6000 even under low light power conditions (30 µW cm−2). The measured photoresponsivity of the devices is much higher than that of inorganic single‐crystal silicon thin film transistors. These studies should boost the development of the organic semiconductors with high‐quality microstructures for potential application in organic optoelectronics.

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In this work, isotherm and kinetics of CO 2 adsorption on a chromium-based metal organic framework MIL-101 sample were studied. The MIL-101 crystal cubes were synthesized by the microwave irradiation method and then characterized. The isotherms and kinetic curves of CO 2 adsorption on the MIL-101 sample were separately measured at 298, 308, 318, and 328 K within a pressure range of 0-30 bar by a gravimetric method. The mass-transfer constants and diffusion activation energy E a of CO 2 adsorption on the MIL-101 crystals were estimated separately. Results showed that the maximum uptake of CO 2 on MIL-101 was 22.9 mmol/g at 298 K and 30 bar and that isotherms of CO 2 adsorption were well-fitted with the Freundlich model. The isosteric adsorption heat of CO 2 on MIL-101 was in the range of 4.0-28.6 kJ/ mol. It depended upon the amount of CO 2 uptake and decreased with the loading of CO 2 . The adsorption kinetics of CO 2 on the MIL-101 crystals was described by the linear driving force (LDF) model. With the increase of the temperature, the mass-transfer constants of CO 2 adsorption on MIL-101 increased. The diffusion coefficients of CO 2 were in the range from 4.11Â10 -11 to 2.54Â10 -10 cm 2 /s. The coefficients increased with the temperature and decreased with the pressure. The diffusion activation energies E a of CO 2 on MIL-101 were in the range of 2.62-4.24 kJ/mol, which decreased with the pressure.

The separation of ethane from ethylene using cryogenic distillation is an energy-intensive process in the industry. With lower energetic consumption, the adsorption technology provides the opportunities for developing the industry with economic sustainability. We report an iron-based metal-organic framework PCN-245 with interpenetrated structures as an ethane-selective adsorbent for ethylene/ethane separation. The material maintains stability up to 625 K, even after exposure to 80% humid atmosphere for 20 days. Adsorptive separation experiments on PCN-245 at 100 kPa and 298 K indicated that ethane and ethylene uptakes of PCN-245 were 3.27 and 2.39 mmol, respectively, and the selectivity of ethane over ethylene was up to 1.9. Metropolis Monte Carlo calculations suggested that the interpenetrated structure of PCN-245 created greater interaction affinity for ethane than ethylene through the crossing organic linkers, which is consistent with the experimental results. This work highlights the potential application of adsorbents with the interpenetrated structure for ethane separation from ethylene.