A family member of tetracene, 2,8-Di-tert-butyl-5,11-bis(4-tert-butylphenyl)-6,12-diphenyltetracene (TBRb) has been widely used as a yellow dopant material in TADF-OLEDs. It is popular because of its bipolar characteristics.
The greater hindrance introduced by four tetra-tert-butyl bulky steric groups (attached to the benzene rings of rubrene) is believed to reduce the chances of concentration-quenching by effectively preventing inter-molecular aggregation of the dopant molecules. In return, this can improve device performance (e.g. in terms of external quantum efficiencies, overall power efficiencies, and lifetime).
*Sublimation is a technique used to obtain ultra pure-grade chemicals. For more details about sublimation, please refer to the Sublimed Materials.