The development of polymeric materials that exhibit blue thermally activated delayed fluorescence(TADF)is of great interest for optoelectronic applications.However,achieving TADF in polymers often requires an elaborat...The development of polymeric materials that exhibit blue thermally activated delayed fluorescence(TADF)is of great interest for optoelectronic applications.However,achieving TADF in polymers often requires an elaborate monomer design.The high-energy local triplet state(^(3)LE)of carbazole complicates its application despite the molecular orbital arrangement being suitable for blue emission.Here,we present an approach to polymer design that makes it possible to solve this problem.We demonstrate the in situ formation of a TADF donor-acceptor system during Suzuki polycondensation,creating an extended carbazole-based donor matrix coupled with a triazine acceptor.The resulting polymer exhibited efficient TADF with a low energy gap(ΔE_(ST))value if a phenyl N-substituent,enabling essential electron delocalization,was present in the carbazole moiety.This work establishes a versatile platform for developing carbazole-based TADF polymers,overcoming the fundamental limitations that hinder their widespread application.展开更多
Copolyfluorenes are of great interest due to their ability to form thin films with tunable optical and electrical properties.In this paper,copolymers of polyfluorene with electron withdrawing dicyanostilbene and dicya...Copolyfluorenes are of great interest due to their ability to form thin films with tunable optical and electrical properties.In this paper,copolymers of polyfluorene with electron withdrawing dicyanostilbene and dicyanophenanthrene moieties were synthesized;their thin films were characterized by electron spectroscopy,cyclic voltammetry,electrical,and photoelectrical measurements.The mobility of charge carriers in the copolymers was measured for the first time,with the acceptor components providing balanced electron and hole mobilities of the order of 10^(-6) cm^(2)·V^(-1)·s^(-1).Photodetectors based on the copolymer/PTCDI heterojunction exhibited the photoresponse band extended into the green region due to the absorption of PTCDI and an increased photocurrent in the UV-blue absorption band of the copolymer,which is related to the absorption of photoluminescent emission of the copolymers in PTCDI.The presented approach to improving the performance of a polymer-based photodetector is promising in organic optoelectronics.展开更多
基金supported by the Russian Science Foundation (No. 25-13-00300)the Centre for Optical and Laser Materials Research (SPbSU) and Saint Petersburg State University for measuring the quantum yields of luminescence within the framework of research project(No.125021902439-8)。
文摘The development of polymeric materials that exhibit blue thermally activated delayed fluorescence(TADF)is of great interest for optoelectronic applications.However,achieving TADF in polymers often requires an elaborate monomer design.The high-energy local triplet state(^(3)LE)of carbazole complicates its application despite the molecular orbital arrangement being suitable for blue emission.Here,we present an approach to polymer design that makes it possible to solve this problem.We demonstrate the in situ formation of a TADF donor-acceptor system during Suzuki polycondensation,creating an extended carbazole-based donor matrix coupled with a triazine acceptor.The resulting polymer exhibited efficient TADF with a low energy gap(ΔE_(ST))value if a phenyl N-substituent,enabling essential electron delocalization,was present in the carbazole moiety.This work establishes a versatile platform for developing carbazole-based TADF polymers,overcoming the fundamental limitations that hinder their widespread application.
基金supported by the Russian Science Foundation(No.23-43-00060)financially supported by the Ministry of Science and Higher Education of the Russian Federation within the framework of the state assignment for scientific activity(No.122011300052-1).
文摘Copolyfluorenes are of great interest due to their ability to form thin films with tunable optical and electrical properties.In this paper,copolymers of polyfluorene with electron withdrawing dicyanostilbene and dicyanophenanthrene moieties were synthesized;their thin films were characterized by electron spectroscopy,cyclic voltammetry,electrical,and photoelectrical measurements.The mobility of charge carriers in the copolymers was measured for the first time,with the acceptor components providing balanced electron and hole mobilities of the order of 10^(-6) cm^(2)·V^(-1)·s^(-1).Photodetectors based on the copolymer/PTCDI heterojunction exhibited the photoresponse band extended into the green region due to the absorption of PTCDI and an increased photocurrent in the UV-blue absorption band of the copolymer,which is related to the absorption of photoluminescent emission of the copolymers in PTCDI.The presented approach to improving the performance of a polymer-based photodetector is promising in organic optoelectronics.
