Efficient near-infrared (NIR) polymer light-emitting diode (PLED) based on the binuclear [(C∧N)2Ir-(bis-N∧O)-Ir(C∧N)2] complex with aggregation-induced phosphorescent enhancement (AIPE) character

In this work, for the obtained NIR-emitting dinuclear [(iqbt)(2)Ir-L-n-Ir(iqbt)(2)] complexes (n = 1-3, 1-3; Hiqbt = 1-(benzo[b]-thiophen-2-yl)-isoquinoline) with the bridging linkages of three flexible bis-(NO)-O-boolean AND-Schiff-base ligands H2Ln, their obvious aggregation-induced phosphorescent enhancement (AIPE) behaviors in powder-form solid or MeCN-H2O mixture are observed, respectively. Moreover, based on the AIPE-switched NIR phosphorescence (Phi(em) = 0.11 and tau = 0.27 mu s) of the diiridium complex 1 without electron-donating substituents in the aggregation state, its solution-processed NIR-PLED is reliably realized, exhibiting the attractive electroluminescent performance with both eta(max)(EQE) = 1.08% and almost negligible efficiency-roll-off.