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Nanocrystals of Cs3Cu2I5, a metal halide with promising potential as a perovskite substitute, are successfully grown on graphene nanosheets. An intermediate stage of physically exfoliated graphene nanosheets, concurrent with the formation of copper‐based seeds on graphene surface, is developed, for the first time, allowing for the subsequent growth of Cs3Cu2I5 nanocrystals (CsNCs) to obtain CsNCs‐decorated graphene nanohybrids (CsGNHs). The morphology and properties of the CsGNHs depend on the input amount of graphene nanosheets during the reaction. The photoluminescence intensity of the CsGNHs decreases with increasing graphene content, indicating that graphene facilitates nonradiative energy transfer from the CsNCs in the CsGNHs. The inherent self‐trapping exciton emission of the CsNCs is also affected by the graphene substrate. As the graphene content increases, the emission peaks of the CsGNHs broaden and diminish. The CsGNHs emit a stable solid‐state luminescence with a large Stokes shift (zero self‐absorption) under a high‐energy ultraviolet (UV) light. Consequently, the CsGNHs can act as optoelectronic transducers and selectively generate a turn‐on photocurrent response under specific‐wavelength UV light. Additionally, a new anticounterfeiting strategy is developed using the CsGNHs as a luminescent black ink to fabricate luminescent quick‐response codes with fake pixels. [ABSTRACT FROM AUTHOR]

Combining the characteristics of different materials offers exciting new opportunities for advanced applications in various fields. Herein, white light‐emitting diodes (WLEDs) with >200% reversible stretchability are fabricated using six‐color quantum dots (QDs) gel emitters. Stable aqueous‐phase alloy core/shell QDs with high quantum yield are obtained via ligand exchange using a ternary solvent system. Transparent and highly stretchable gels with large pores are created by binary‐solvent‐based gelation at low temperatures. Importantly, the QDs and the gel originate from the same two solvents, which make the QDs highly compatible with the gelation process. Consequently, QDs of six different colors are incorporated into the gel without any property degradation. The excellent optical properties of the QDs in the liquid phase (e.g., 17% higher photoluminescence (PL) intensity) are retained in the gel phase. The QD gel (QDG) exhibits elastic deformation up to 200%, with uniform PL over the entire gel. A down‐conversion WLED built using the QDG emitter produces cool white light with a color temperature of 6100 K, a color rendering index of 94, and a luminous efficacy of 72 lm W−1. In addition, the performance of the QDG‐based WLED remains unchanged even after more than 1000 bending/stretching cycles. [ABSTRACT FROM AUTHOR]

The article reports on asymmetric aldol reaction catalyzed by L-Proline and Achiral Thiourea Fluoroboric Acid Salt. Topics discussed include the aldol reaction, challenges due to its stereoselectivity and proline. Additional topics discussed include major drawbacks of proline, alternatives and isothiouroniums to enhance the acidity of the NH moieties and allow more hydrogen bonding.

The article presents the process to accomplish the Asymmetric Aldol Reaction Catalyzed by L-Proline and Achiral Thiourea Fluoroboric Acid Salt and describes the chemical equations in this process.