Thermally activated delayed fluorescence polymers for high-efficiency solution-processed non-doped OLEDs: Convenient synthesis by binding TADF units and host units to the pre-synthesized polycarbazole-based backbone via click reaction

At present, TADF polymers with multiple functional components are still limited due to their complicated synthetic process and low synthetic repeatability. To overcome these problems, a post-functionalization strategy was exploited to synthesize the self-host TADF conjugated polymers. A series of yellow-green TADF polymers, PCz-mCP-PxzTrz-X, X = 10, 20, 30 or 40, were successfully synthesized by grafting stoichiometric TADF units (phenoxazinetriphenyltriazine, PxzTrz) and host units (1,3-bis(N-carbazolyl)benzene, mCP) onto the side chain of a pre-synthesized polycarbazole-based backbone via a click reaction. The carbazole-containing main chain and mCP-containing side chains served as an encapsulant , which can transport carriers and prevent the TADF units from concentration quenching. Using PCz-mCP-PxzTrz-30 as the light-emitting layer, the solution-processed non-doped organic light-emitting diode displayed an external quantum efficiency of 15.2% at 100 cd m(-2). Our synthetic method could offer a useful strategy to construct self-host TADF polymers containing multiple functional components.

Automated summary

A post-functionalization strategy was used to synthesize self-host TADF conjugated polymers, which successfully addressed the issues of complicated synthetic process and low synthetic repeatability for TADF polymers with multiple functional components.