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The nonradiative recombination of electrons and holes has been identified as the main cause of energy loss in hybrid organic-inorganic perovskite solar cells (PSCs). Sufficient built-in field and defect passivation can facilitate effective separation of electron-hole pairs to address the crucial issues. For the first time, we introduce a homochiral molecular ferroelectric into a PSC to enlarge the built-in electric field of the perovskite film, thereby facilitating effective charge separation and transportation. As a consequence of similarities in ionic structure, the molecular ferroelectric component of the PSC passivates the defects in the active perovskite layers, thereby inducing an approximately eightfold enhancement in photoluminescence intensity and reducing electron trap-state density. The photovoltaic molecular ferroelectric PSCs achieve a power conversion efficiency as high as 21.78 %., (© 2020 Wiley-VCH GmbH.)

A novel asymmetric catalytic approach for the construction of enantioenriched functionalized 1,2-dihydropyridines and pyridine derivatives incorporating adjacent quaternary and tertiary stereocenters has been reported. This process involved a metal-free catalytic asymmetric allylic alkylation and a stereospecifically nonoxidative aromatization approach for the desired chiral molecules.

In this study, water-soluble silicon quantum dots have quasi-blue emission at 390 nm by being capped with 1-vinylimidazole in resese micelles. As-obtained silicon quantum dots have a diameter of 2~5 nm and high crystallinity. The quasi-blue emission of the silicon quantum dots is likely attributed to the polarity of the capping ligands. Moreover, the silicon quantum dots are water-soluble and have photoluminescence nanosecond decay time, suggesting their potential application in biological field.

Pyrrolidine rings are common moieties for pharmaceutical candidates and natural compounds, and the construction of these skeletons has received much attention. α-Amino nitriles are versatile intermediates in synthetic chemistry and have been widely used in the generation of multiple polyfunctional structures. Herein, a novel nucleophilic phosphine-catalyzed intramolecular Michael reaction of N-allylic substituted α-amino nitriles has been developed for the efficient construction of functionalized 2,4-disubstituted pyrrolidines (N-heterocyclic α-amino nitriles) via 5-endo-trig cyclization. Furthermore, the one-pot sequence of the synthesis of pyrrolidine and the subsequent transformations of the functionalized products have also been demonstrated.

The first tertiary amine catalyzed asymmetric allylic amination/cycloaddition cascade sequence has been developed, which provided a novel protocol to construct enantioenriched azapolyheterocycles under mild reaction conditions efficiently (up to 95% ee, endo/exo >20:1).

In this tutorial article, the recent development of polymer assisted deposition (PAD) for the growth of a wide range of materials, in particular in thin films, is reviewed. Specifically, we describe the unique chemistry and processes of PAD for the deposition of metals, metal-oxides, metal-nitrides, metal-carbides, and their derived composites. Many examples are given not only to illustrate the powerfulness of PAD for high quality coatings, but also to give readers an opportunity to evaluate this technique for specific applications. The challenging issues related to PAD, based on the authors' experience, are also discussed in this review article.

The formation of carbon nanotube and superconductor composites makes it possible to produce new and/or improved functionalities that the individual material does not possess. Here we show that coating carbon nanotube forests with superconducting niobium carbide (NbC) does not destroy the microstructure of the nanotubes. NbC also shows much improved superconducting properties such as a higher irreversibility and upper critical field. An upper critical field value of ~5 T at 4.2 K is much greater than the 1.7 T reported in the literature for pure bulk NbC. Furthermore, the aligned carbon nanotubes induce anisotropy in the upper critical field, with a higher upper critical field occurring when the magnetic field is parallel to the carbon nanotube growth direction. These results suggest that highly oriented carbon nanotubes embedded in superconducting NbC matrix can function as defects and effectively enhance the superconducting properties of the NbC.