Controlling chemical reactions by the supramolecular confinement effects of nanopores has attracted great attention. Here we show that open metal sites in porous coordination frameworks can constitute more powerful and strict templates for precision syntheses. A Fe(III) dicarboxylate framework functionalized with triangularly arranged metal sites is used to accomplish [2+2+2] cyclotrimerization reactions for organonitrile, alkyne and alkene monomers bearing a geometrically suitable pyridyl group. In situ single-crystal X-ray diffraction facilitates the direct observation of such a coordination templated reaction, before cylcotrimerization, the monomer coordinates at the Fe(III) centre by its pyridyl donor, which forces three unsaturated groups to gather around a position very similar with that of the desired covalent cyclic trimer. After the reaction, the trimers serve as tripodal ligands to perfectly fix the Fe(III) ions and the whole crystal to generate an exceptionally rigid and porous material with large surface area coupled with guest-proof zero thermal expansion.

Two asymmetric three-dimensional (3D) holetransporting materials (HTMs) containing a triphenylethylene core and peripheral diphenylamine/triphenylamine moieties are first synthesized and successfully used in perovskite solar cells (PSCs). Both HTMs are obtained from facile preparation procedures and simple purification techniques. The X-ray diffraction, aggregation-induced emission properties, absorption and emission spectra, electrochemical properties, thermal stability, density functional theory calculations, hole mobility, scanning electronic microscopy, atomic force microscopy, steady-state and time-resolved photoluminescence, water contact angles, and photovoltaic parameters of the PSCs are compared. The highest power conversion efficiency increases from 12.57% (CJ-02) to 18.56% (CJ-01), rivaling that obtained from the state-of-the-art 2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenylamine)-9,9′-spirobifluorene (spiro-OMeTAD) (18.69%). Further, the lab synthetic cost of CJ-01 is only about 15.5% of the price of commercial spiro-OMeTAD, and the concentration of CJ-01 solution for device fabrication is less than half of the concentration of spiro-OMeTAD solution (30.0 vs 72.3 mg mL −1 ). These results demonstrate that the propeller-shaped compounds with a highly twisted conformation are readily available and promising alternative HTMs for PSCs. Moreover, an applicable strategy to design new HTMs with 3D structure for achieving highly efficient PSCs is proposed.

The under-coordinated defects within perovskite and its relevant interfaces always attract and trap the free carriers via the electrostatic force, significantly limiting the charge extraction efficiency and the intrinsic stability of perovskite solar cells (PSCs). Herein, self-diffusion interfacial doping by using ionic potassium L-aspartate (PL-A) is first reported to restrain the carrier trap induced recombination via the reconstruction of energy level structure at SnO 2 /perovskite interface in conventional n-i-p structured PSCs. Experiments and theories are consistent with the PL-A anions that can remain at the SnO 2 surface due to strong chemical adsorption. During the spin-coating of the perovskite film, the cations gradually diffuse into perovskite and endow an n-doping effect, which provides higher force and a better energy level alignment for the carrier transport. As a result, they obtained 23.74% power conversion efficiency for the PL-A modified small-area devices, with dramatically improved open-circuit voltage of 1.19 V. The corresponding large-area devices (1.05 cm 2 ) achieved an efficiency of 22.23%. Furthermore, the modified devices exhibited negligible hysteresis and enhanced ambient air stability exceeding 1500 h.

A series of novel phenyl pyrazole inner salt derivatives based on fipronil were designed and synthesized in the search for dual-target insecticides. These compounds were designed to target two families of nicotinic acetylcholine receptors and γ-aminobutyric acid receptors. The insecticidal activities of the new compounds against diamondback moth (Plutella xylostella) were evaluated. The results of bioassays indicated that most of the inner salts showed moderate to high activities, of which the phenyl pyrazole inner salts containing quinoline had excellent biological activity. Previous structure-activity relationship studies revealed that a suitable structure of the quaternary ammonium salts was critical for the bioactivity of phenyl pyrazole inner salts, which contribute to exposing the cationic nitrogen to bind to the receptor (for instance, nicotinic acetylcholine receptors) and possibly interact with the receptor via hydrogen bonding and cooperative π-π interaction. The present work demonstrates that the insecticidal potency of phenyl pyrazole inner salts holds promise for the development new dual-target phenyl pyrazole insecticides.

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In this work, yolk-shell structured magnetic hollow mesoporous silica (MHMS) nanospheres with controllable magnetic responsibility, high specific surface area, a huge cavity and ink-bottle type mesopores were successfully synthesized in one-step by an electrostatic self-assembly templated approach. The obtained MHMS nanospheres exhibited low cytotoxicity, excellent biocompatibility and potential application in the biomedical field.

A highly sensitive and selective colorimetric assay for Hg2+ and Ag+ was developed using core–shell Au@Pt nanoparticles.