Benzene-cored fluorophors with TPE peripheries: facile synthesis, crystallization-induced blue-shifted emission, and efficient blue luminogens for non-doped OLEDs

In this paper, three benzene-cored fluorophors with TPE moiety peripheries (PhTPE, Ph2TPE and Ph3TPE), are synthesized and their thermal, optical and electronic properties are investigated. All of them are nearly non-emissive when readily dissolved in solution but become highly emissive in the aggregate state, making them promising candidates for optoelectronic materials. Non-doped OLEDs with these luminogens as emissive layers exhibit sky-blue to deep blue emissions from 488 to 457 nm with Lmax, ηC, max and ηP, max up to 3966 cd m−2, 5.0 cd A−1 and 3.87 lm W−1, respectively, owing to the twisted conformation between the benzene core and TPE units.