Abstract
Chiral organometallic Pt(ii) complexes have been demonstrated to be excellent circularly polarized luminescence (CPL) materials due to their rich phosphorescence and strong self-assembly characteristics. However, it remains a formidable task to simultaneously achieve high luminance (L) and electroluminescence dissymmetry factor (g (EL)) values for circularly polarized electroluminescence (CP-EL) devices of Pt(ii) complex-based emitters. In this study, we carry out a straightforward and efficient protocol to construct highly CPL-active helical columnar () emitters by using chiral homoleptic triazolatoplatinum(ii) metallomesogens (R/S-HPt). The peripheral flexible groups can not only improve solubility but also favor the induction of chirality and liquid crystal behavior. The resultant complexes R/S-HPt can self-assemble into the mesophase over a broad temperature range (6-358 °C) and exhibit excellent phosphorescence (Φ: up to 86%), resulting in intense CPL signals after thermal annealing (λ (em) = 615 nm and |g (em)| = 0.051). Using emitting layers (EML) based on R/S-HPt in solution-processed CP-EL devices, L (max) and |g (EL)| of CP-EL can reach up to 11 379 cd m(-2) and 0.014, respectively. With comprehensive consideration of L (max) and g (EL), this investigation shows the excellent performances among Pt(ii) complex-based CP-EL devices.