Molecular designs merging circularly polarized luminescence (CPL) and thermally activated delayed fluorescence (CP-TADF) using the concept of chiral perturbation appeared recently as a cornerstone for the development of efficient CP-organic light emitting diodes (CP-OLED). Such devices could strongly increase the energy efficiency and performances of conventional OLED displays, in which 50% of the emitted light is often lost due to the use of antiglare filters. In this context, herein, ten couples of enantiomers derived from novel chiral emitter designs are reported, exhibiting CPL, TADF, and aggregation induced enhancement emission properties (AIEE). Representing the first structure properties relationship investigation for CP-TADF materials, this thorough experimental and theoretical work highlights crucial findings on the key structural and electronic parameters (isomerism, nature of the carbazole substituents) governing the synergy between CPL and TADF properties. To conclude this study, the first top emission CP-OLED is elaborated as a new approach of generating CP light in comparison with classical bottom-emission CP-OLED architecture. Indeed, the top-emission configuration represents the only relevant device architecture for future microdisplay applications. Thereby, in addition to offer molecular guidelines to combine efficiently TADF and CPL properties, this study opens new avenues toward practical applications for CP-OLEDs.
Modulation and fine‐tuning of the strength of weak interactions to bind anions are described in a series of synthetic receptors. The general design of the receptors includes both a urea motif and a tetrazine motif. The synthetic sequence towards three receptors is detailed. Impacts of H‐bond strength and linker length between urea and tetrazine on chloride complexation are studied. Binding properties of the chloride anion are examined in both the ground and excited states using a panel of analytical methods (NMR spectroscopy, mass spectrometry, UV/Visible spectroscopies, and fluorescence). A ranking of the receptors by complexation strength has been determined, allowing a better understanding of the structure‐properties relationship on these compounds.
Anion recognition represents an intense area of research in supramolecular chemistry. The last two decades have been marked by spectacular advances in the design of new anion receptors. Moreover, the development of approaches combining Jean-Yves Salpin got his PhD in chemistry from the University of Orsay in 1997. Then, from 1997 and 1999, he held postdoctoral positions at the University of Bielefeld (Germany) and at the Catholic University of Leuven (Belgium). Back in France, he works since 1999 as a full research scientist at the Centre National pour la Recherche Scientifique (CNRS). His research interests lie in the field of gas-phase ion chemistry by combining mass spectrometry and quantum chemistry. Promoted CNRS senior research scientist in 2012, his major field of research concerns the reactivity of metal ions (alkalineearth, transition metal, heavy metals) towards organic molecules or biomolecules, and more recently the study of interactions of both anionic and cationic receptors.
The Front Cover shows the combination of anion‐π interaction and hydrogen bonding, which provides some synergistic effects called “cooperativity”. On this cover picture, this recent concept of supramolecular chemistry is illustrated by two characters that help each other to select and recognize anions of different size and shapes. The cartoon was created by Mrs. Naseem Farzand. More information can be found in the Review by R. Plais et al.
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