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Based on the charge-polarity control, a novel anti-ambipolar heterotransistor is proposed based on a special In2Se3&WSe2 van der Waals heterostructure. Unlike traditional logic transistors, our anti-ambipolar heterotransistor can treat an...

Iron-based porphyrinic metal–organic frameworks (PMOFs) are desirable for biomimetic applications, due to the low toxicity and high abundance of Fe as well as the rich biomimetic functions of metalloporphyrins. Besides, the uniform dispersion of porphyrin centers in PMOFs can effectively protect them from self-dimerization. Nevertheless, it remains a big challenge to synthesize iron-based PMOFs. In this study, a series of Fe–oxo chain-based PMOFs incorporating different metals in porphyrinic centers (namely M-PMOF-3(Fe), M = Fe, Co, Ni, Cu) are synthesized directly from the reaction of metalloporphyrin and iron salts with an improved modulating strategy using a pair of monocarboxylic acids and water as the three-component modulator. The prepared materials of M-PMOF-3(Fe) possess high stability to resist a broad pH range (0–11) and even 2 M HCl in aqueous solutions for 2 days, and their frameworks can be maintained up to 350 °C. Catalytic tests show that M-PMOF-3(Fe) are effective in the aerobic oxidation of C–H bonds using oxygen from the air as the oxidant.

It is of significant importance to capture and separate organic pollutants from water sources to combat the growing environmental problems. Advanced sorbent materials with rapid, high-capacity and selective sorption performances are desirable. Herein, a coordination framework (LIFM-WZ-4) containing micro-channels with a large percentage (70%) of “naked” nitrogens is reported, affording donor–acceptor (D–A) interaction abilities with specific selectivity for electron-deficient CO2 gases or cationic dyes. Especially, although with a neutral network, exclusively selective, fast and large adsorption capacities for cationic dyes from aqueous solutions were achieved, with a record high value of 1492.0 mg g−1 for MB+ among the materials reported to date. The underlying adsorption mechanism was probed from both kinetic and thermodynamic considerations, revealing a pseudo-second-order kinetic model and a D–A inducing chemisorption process accounting for the unique selectivity. The saturated sorbent can then be readily recovered by dye release in CH3CN. This easy recyclability provides potential for practical applications in water sanitation and dye separation.

The facile preparation of hyperbranched glycopolymers was performed without protecting group chemistry, where the methyl-6-O-methacryloyl-α-D-glucoside (6-O-MMAGlc) monomer was adopted as an AB3*-type inimer. The polymerization was initiated by the hydroxy/cerium(IV) redox process and could be named the self-condensing vinyl copolymerization/redox (SCVP/Redox) process. The oxygen radical (C–O˙), rather than the carbon radical (˙C–OH), was generated by the redox reaction of Ce(IV) with –OH groups on the pyranose in 6-O-MMAGlc, which was confirmed by NMR data. The formation of the branching point and linear chain growth were defined to give the degree of branching (DB). A linear increase of the DB was observed as the concentration of Ce(IV) increased, implying facile control of the DB. More interestingly, the hyperbranched glycopolymers on the amyloid fibrillation of hen egg-white lysozyme (HEWL) exhibited a greater inhibition activity than that of the linear analogue. This substantial study would provide more room to enrich the family of glycopolymers and extend their potential application in biomedicine and biomaterials.

A novel selenadiazole-fused pyrene derivative PySe was successfully synthesized and characterized. Its single structure is almost planar and adopts a sandwich-herringbone packing model. The self-assembly behaviors based on compound PySe and its analogue thiadiazole-fused pyrene derivative PyS were studied in detail and the as-formed nanostructures were fully characterized by means of UV-vis absorption, emission spectra, X-ray diffraction, field emission SEM and TEM. We attribute the bathochromic shift absorption and emission spectra of PyS and PySe in aqueous solution to the formation of J-type aggregation. In addition, our investigation demonstrated that the shape and size of the as-prepared nanostructures could be tuned by different chalcogen analogues and the volume ratio of water to organic solvent.

In this paper, we have developed a “green” method for the synthesis of metal telluride nanocrystals. In this method, di-n-octylphosphine oxide (DOPO) has been used to disperse Te and form Te–DOPO precursor. This new Te precursor was found to be highly reactive and suitable for the synthesis of metal telluride nanocrystals in various monodispersity, size, and shape. Dot-/tetrapod-shaped CdTe, dot-shaped ZnTe, dot-/cubic-shaped PbTe, dot-/rod-shaped Ag2Te, cubic-shaped Cu2−xTe, ternary alloyed CuInTe2, and quaternary alloyed Cu2ZnSnTe4 semiconductor nanocrystals all have been well-controlled synthesized. The photoluminescence emission of as-synthesized CdTe nanocrystals covered a wide range (570–735 nm) and the quality of as-synthesized metal telluride nanocrystals were reached or exceed the level compared with the traditional method using phosphine–Te precursor. The possible dissolving molecular mechanism of Te in DOPO in this synthesis was specially studied and illustrated that intramolecular proton transfer from the phosphorus (formation of DOPO–Te complex) was essential in the synthesis of metal telluride nanocrystals. This method provided a greener and less expensive route to large-scale synthesis of all kinds of high quality metal telluride nanocrystals.

A structurally flexible porous metal–organic framework, [CuII(bped)2(H2O)2(SiF6)] ⊃ 4H2O (Cu-MOF-SiF6) was prepared from CuSiF6 and meso-1,2-bis(4-pyridyl)-1,2-ethanediol (bped) in EtOH–H2O. Cu-MOF-SiF6 is a three-dimensional (3D) polycatenated framework consisting of two-dimensional (2D) (4,4) topological grid networks which display 2-fold inclined interpenetration in the crystal lattice. The SiF62− anions hosted in the one-dimensional channels of Cu-MOF-SiF6 can be readily exchanged with NO3− anions while keeping the framework intact, leading to isomorphous Cu-MOF-NO3. The Cu-MOFs show selective adsorption behaviors due to the host–guest interaction, which is dependent on the anions and the guest size. The MeOH uptake investigation indicates that Cu-MOF-SiF6 demonstrates a breathing effect, while Cu-MOF-NO3 exhibits distinctive stepwise MeOH sorption due to the smaller size of NO3− and the larger voids in the crystal lattice. Cu-MOF-NO3 also exhibits stepwise sorption for larger EtOH guests, while the uptake of EtOH is blocked in Cu-MOF-SiF6. In addition, the solids show anion-responsive catalytic properties. Both Cu-MOF-SiF6 and Cu-MOF-NO3 efficiently oxidize benzylic compounds to the corresponding carbonyl functionality under mild and convenient reaction conditions, but improved catalytic activity was observed for Cu-MOF-NO3. The catalysts can be reused with the framework left intact at least three times without losing of any activity.