Exploring the design principle for switching thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP) is a fundamentally imporant research in developing triplet-mediated photofunctional organic materials. Herein systematic studies...

A new family of thermally activated delayed fluorescence (TADF) emitters based on a twisted donoracceptor (DÀ A) dyad scaffold comprising of dihydrophenazasiline (D) and pyrido[2,3-b]pyrazine (A) has been developed, and their properties have been investigated. Time-resolved spectroscopic analysis in matrices revealed the detailed photophysical properties of the DÀ A compounds. These DÀ A compounds serve as the emitter for organic light-emitting diodes (OLEDs), showing a moderate external quantum efficiency (EQE) up to 9% in CBP matrix. Furthermore, theoretical calculations uncovered the excited states nature of the developed TADF emitters.

A dual-photofunctional organogermanium compound based on a donor–acceptor–donor architecture that exhibits thermally activated delayed fluorescence and mechano-responsive luminochromism has been developed. The developed compound was successfully applied as an emitter...

Previous work has reported the synthesis of donor–acceptor–donor molecules based on dibenzophenazine acceptor group, presenting thermally activated delayed fluorescent (TADF) properties and their application in the assembly of highly efficient electroluminescent devices. Herein, we focus on the characterisation of charge carrier species through UV‐Vis‐NIR spectroelectrochemical and potentiostatic EPR techniques, in addition to the investigation of electropolymerisation properties of some compounds depicted in this study. The promising electrochromic features of both small molecules and conjugated polymers led to the assembly and investigation of electrochromic devices, evidencing the materials’ versatility, applied in such different approaches as electrochromic windows and electroluminescent devices. Furthermore, the assembled OLEDs provided high efficiencies, with small roll‐off, EQEs up to 20.5 % and luminance values up to 85 000 cd/m2.

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Exploring design principle for switching thermally activated dealyed fluorescecne (TADF) and room temperature phosphorescence (RTP) is a fundamentally imporant research in developing triplet-mediated photofunctional organic materials. Herein systematic studies on the regioisomeric and substituents effects in a twisted donor–acceptor–donor (D–A–D) scaffold (A = dibenzo[a,j]phenazine; D = dihydrophenazasiline) on the fate of the excited state have been performed. The study revealed that the regiosiomerism clearly affects the emission behavior of the D–A–D compounds. Distinct difference in TADF, dual TADF & RTP, and dual RTP were observed, depending on the host used. Furthermore, OLED organic light-emitting diodes (OLEDs) fabricated with the developed emitters achieved high external quantum yields for RTP-based OLEDS up to 7.4%.