High-color-purity, efficient, and long-lifetime organic light-emitting devices have been successfully developed. The optimized device realized an FWHM of 32 nm, CIE of (0.28, 0.67), EQEmax of nearly 19%, and LT50 of 14 000 h at 1000 cd m−2.

A series of tetrapyridine/triazine-conjugated electron transporters, TnPyTRZ, was developed. T3PyTRZ realized a turn-on voltage of 2.18 V, power efficiency of over 115 lm W−1, and lifetime of 30 000 h at 1000 cd m−2 in green phosphorescent OLED.

A four dibenzofuran-terminated hole-transporter, T1DBFBP, realizes high-efficiency and highly stable green TADF OLEDs with an EQE of over 20% and a long operation lifetime LT50 of 30 000 h at 1000 cd m−2.