The sulfur atoms positions in three isomers play an important role in the intermolecular interactions and OFET performances.

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Precise design and construction of catalysts with satisfied performance for ambient electrolytic nitrogen reduction reaction (e-NRR) is extremely challenging. By in situ integrating an electron-rich polyoxometalates (POMs) into stable metal organic frameworks (MOFs), five POMs-based MOFs formulated as [Fe x Co y (Pbpy) 9 (ox) 6 (H 2 O) 6 ][P 2 W 18 O 62 ]•3H 2 O (abbreviated as Fe x Co y MOF-P 2 W 18 ) are created and directly used as catalysts for e-NRR. Their electrocatalytic performances are remarkably improved thanks to complementary advantages and promising possibilities of MOFs and POMs. In particular, NH 3 yield rates of 47.04 µg h −1 mg cat. −1 and Faradaic efficiency of 31.56% by FeCoMOF-P 2 W 18 for e-NRR are significantly enhanced by a factor of 4 and 3, respectively, compared to the [Fe 0.5 Co 0.5 (Pbpy)(ox)] 2 •(Pbpy) 0.5 . The cyclic voltammetry curves, density functional theory calculations and in situ Fouriertransform infrared spectroscopy confirm that there is a directional electron channel from P 2 W 18 to the MOFs unit to accelerate the transfer of electrons. And the introduction of bimetals Fe and Co in the P 2 W 18 -based MOFs can reduce the energy of the *N 2 to *N 2 H step, thereby increasing the production of NH 3 . More importantly, this POM in situ embedding strategy can be extended to create other e-NRR catalysts with enhanced performances, which opens a new avenue for future NH 3 production for breakthrough in the bottleneck of e-NRR.

A highly reactive and selective chemodosimetric probe for cyanide was synthesized based on alkylidene Meldrum's acid as a novel cyanide reaction site. A theoretical study was conducted to rationalize the high reactivity and the photophysical properties of probe 1 and the 1-CN adduct.

A novel 2,2':6',2''-terpyridine-based ligand L and its complexes [ML(2)](ClO(4))(2)·CH(2)Cl(2) (M = Cd 1, Zn 2, Cu 4, Mn 5), [CoL(2)](ClO(4))(2)3, CdLI(2)6 and CdL(SCN)(2)7 were synthesized and fully characterized. The crystal structures of 1-6 were solved by single crystal X-ray diffraction analysis. The linear absorption and emission properties, and third-order nonlinear optical (NLO) properties of all the complexes were systematically investigated. The equilibrium of the trans- and cis- isomers of L was studied both experimentally and theoretically. The configurations and photophysical properties of the complexes display a large dependence on the choice of metal ions and anions.

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Effective protection against photooxidation of organic wide‐bandgap semiconductors is a potential method to afford high efficient deep‐blue emission for full color displays. Herein, the crystallization effect of fluorene‐based blue emitter on suppressing the formation of long‐wavelength green band (g‐band) defect is demonstrated through the model of self‐assembled organic micro/nanocrystals. The selected molecule 2,2'‐bi(9,9‐dipropyl)fluorene (DDC3F), which easily generates strong g‐band emission (green index (Igreen/Iblue) of ≈5 under ultraviolet exposure for 3 h) in amorphous state, shows an excellent spectra stability of deep‐blue emission with a green index of ≈0 and an unchangeable CIE coordination of (0.18, 0.09) in crystalline nanorod morphologies. Such effect of crystallization‐induced stability enhancement can be further extended into other solution‐processing methods such as brushing. Molecular dynamic simulation reveals that crystalline nanorods with compact molecular packing enable to effectively block the diffusion of O2 and H2O molecules, which is crucial to suppress the occurrence of photooxidation reactions. Along with high quantum yield of 87% from crystallization‐induced luminescence enhancement effect, such ultrastable deep‐blue emission on crystalline film can also be maintained in solution‐processing organic light‐emitting diode devices. The supramolecular self‐assembled micro/nanocrystals strategy provides a potential platform to maintain ultrastable color purity in organic optoelectronic devices.

AM1 semi-empirical method was used to optimize the barbituric acid derivatives substituted with glucosyl B 1-5 (series B), and the thiobarbituric acid derivatives substituted with glucosyl T 1-5 (series T). Based on the optimized structures, INDO/CI method was adopted to calculate the electronic spectra. Meanwhile, the second-order nonlinear optical (NLO) coefficients β µ were calculated with the sum-over-state (SOS) formula. The results show that when the number of glucosyl units was increased, |β µ | values of the barbituric and thiobarbituric acid derivatives were both enhanced, especially for thiobarbituric acid derivatives. It indicates that non-conjugated substituted group could also improve NLO properties of materials when the number of repeated units was increased. Additionally, the absorption bands appearing in UV area are consistent with the proper change of the number of glucosyl units, and consequently it can be concluded that the high transparencies of all systems were scarcely varied.