Efficient helical columnar emitters of chiral homoleptic Pt(<sc>ii</sc>) metallomesogens for circularly polarized electroluminescence

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 (Col*h) emitters by using chiral homoleptic triazolatoplatinum(II) II ) metallomesogens (R/S-HPt). 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 Col*h mesophase over a broad temperature range (6-358 degrees C) and exhibit excellent phosphorescence (F: up to 86%), resulting in intense CPL signals after thermal annealing (lambda(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 11379 cd m( -2 )and 0.014, respectively. With comprehensive consideration of L (max) and gEL, this investigation shows the excellent performances among Pt(II) complex-based CP-EL devices.