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Two synthetic organic dyes of the Benzothioxanthene imide (BTI) family are explored as a promising electroactive material for organic light‐emitting electrochemical cells (LECs). The high thermal stability and ease of thin film processing make BTI‐based compounds suitable for these devices. However, their planar π‐conjugated structure often leads to aggregation‐caused quenching (ACQ), reducing luminescence in the solid state. To overcome this, this study has taken advantage of host‐guest interactions with 4,4′‐bis(9H‐carbazol‐9‐yl) biphenyl (p‐CBP), poly(9‐vinylcarbazole) (PVK), and poly(dioctylfluorene) (PFO) to suppress ACQ. The use of p‐CBP improved the internal electrical double layer (EDL) alignment within the film, resulting in higher luminescence compared to PFO and PVK‐based LECs. The BTI‐F dye, when incorporated into a dual host system with p‐CBP and PFO, achieved an impressive luminescence of up to 3900 cd m−2. Additionally, PFO enhanced charge balance, contributing to a blue shift in maximum absorption wavelength and increasing the device's tolerance. A triple‐host system (p‐CBP, PVK, PFO) further extended the device's half‐life (t1/2) to 54 min, demonstrating the potential of these host‐guest systems in advancing metal‐free LEC technology. [ABSTRACT FROM AUTHOR]

Displays have become ubiquitous in our modern and highly interconnected lives. Complex vacuum processed multi‐stacks are widely integrated into high tech, high value products such as smart phones, while solution processed large area single‐layer OLEDs appear more adequate for basic applications focusing on recyclability such as packaging, road signage, advertising, and single‐use health care products. In this context, we report herein the design, synthesis, and characterization of an accessible series of oligothiophenes end‐capped triphenylamines that were preprepared by atom‐economical direct (hetero)arylation reactions and successfully used as emitter in solution processed devices, from lab scale to large area printed and flexible demonstrator. [ABSTRACT FROM AUTHOR]

Controlling the formation of photoexcited triplet states is critical for many (photo)chemical and physical applications. Here, we demonstrate that a permanent out‐of‐plane distortion of the benzothioxanthene imide (BTI) dye promotes intersystem crossing by increasing spin‐orbit coupling. This manipulation was achieved through a subtle chemical modification, specifically the bay‐area methylation. Consequently, this simple yet efficient approach expands the catalog of known molecular engineering strategies for synthesizing heavy atom‐free, dual redox‐active, yet still emissive and synthetically accessible photosensitizers. [ABSTRACT FROM AUTHOR]

This article, titled "Driving Triplet State Population in Benzothioxanthene Imide Dyes: Let's twist!" explores a chemical modification technique that induces a permanent out-of-plane distortion in the π-conjugated backbone of a benzothioxanthene imide (BTI). The researchers found that this strategy effectively manipulates triplet formation and provides insights into the connection between spin-orbit coupling, twisting of the π-system, and intersystem crossing. The full research article provides more detailed information on this topic. [Extracted from the article]