Semiconductor quantum dots (QDs) have attracted tremendous attention in the field of photocatalysis, owing to their superior optoelectronic properties for photocatalytic reactions, including high absorption coefficients and long photogenerated carrier lifetimes. Herein, by choosing 2‐(3,4‐dimethoxyphenyl)‐3‐oxobutanenitrile as a model substrate, we demonstrate that the stereoselective (>99 %) C−C oxidative coupling reaction can be realized with a high product yield (99 %) using zwitterionic ligand capped CsPbBr3 perovskite QDs under visible light illumination. The reaction can be generalized to different starting materials with various substituents on the phenyl ring and varied functional moieties, producing stereoselective dl‐isomers. A radical mediated reaction pathway has been proposed. Our study provides a new way of stereoselective C−C oxidative coupling via a photocatalytic means using specially designed perovskite QDs.

CO2‐Reduktion. Polymere NHC‐Liganden verbessern die Katalyseeffizienz und Lebensdauer von Au‐ und Pd‐Nanokatalysatoren zur CO2‐Elektroreduktion, wie B. Liu, J. He et al. im Forschungsartikel auf S. 15981 ff. zeigen.

Self-assembly of nanocrystals is a promising route for creating macroscale materials that derive function from the properties of their nanoscale building blocks. While much progress has been made assembling nanocrystals into different superlattices, controlling the relative orientations of nanocrystals in those lattices remains a challenge. Here, we combine experiments with computer simulations to study the self-assembly of patchy heterostructural nanocrystals (HNCs), consisting of near-spherical quantum dots decorated with regular arrangements of small gold satellites, into close-packed superlattices with pronounced orientational alignment of HNCs. Our simulations indicate that the orientational alignment is caused by van der Waals interactions between gold patches and is sensitive to the interparticle distance in the superlattice. We demonstrate experimentally that the degree and type of orientational alignment can be controlled by changing ligand populations on HNCs. This study provides guidance for the design and fabrication of nanocrystal superlattices with enhanced structural control.

Smart materials with coupled optical and mechanical responsiveness to external stimuli, as inspired by nature, are of interest for the biomimetic design of the next generation of soft machines and wearable electronics. A tough polymer that shows adaptable and switchable mechanical and fluorescent properties is designed using a fluorescent lanthanide, europium (Eu). The dynamic Eu-iminodiacetate (IDA) coordination is incorporated to build up the physical cross-linking network in the polymer film consisting of two interpenetrated networks. Reversible disruption and reformation of Eu-IDA complexation endow high stiffness, toughness, and stretchability to the polymer elastomer through energy dissipation of dynamic coordination. Water that binds to Eu 3+ ions shows an interesting impact simultaneously on the mechanical strength and fluorescent emission of the Eu-containing polymer elastomer. The mechanical states of the polymer, along with the visually optical response through the emission color change of the polymer film, are reversibly switchable with moisture as a stimulus. The coupled response in the mechanical strength and emissive color in one single material is potentially applicable for smart materials requiring an optical readout of their mechanical properties.

Carbon quantum dots grafted silica nanoparticles with high production yield and versatile photoluminescence are directly fabricated from rice husks.

Adding metals in synthetic polymers is of broad interest to design multifunctional materials, particularly harnessing unique properties and functionalities not found in pure organic polymers. Other than simple emergence of...

Polymer NHC ligands enhance the catalytic activity of metal nanoparticles despite the increase of surface crowdedness.

We report polymer-promoted cooperative catalysis of Cu for oxygen activation. A series of random copolymers containing dipicolylamine as binding motifs are designed to coordinate type-3 Cu sites. The Cucopolymers show a 6−8-fold activity enhancement, compared to the molecular complex of Cu with an identical coordination site. Michaelis−Menten analysis demonstrates that the kinetic enhancement results from flexible polymer-promoted cooperative catalysis among multi-Cu sites despite the imposed thermodynamic barrier. These observations provide guidance for the bioinspired design of metallopolymers as soluble catalysts with high activity.Communication pubs.acs.org/JACS