An efficient and weak efficiency-roll-off near-infrared (NIR) polymer light-emitting diode (PLED) based on a PVK-supported Zn2+- Yb3+- containing metallopolymer

摘要

Based on copolymerization of NVK (N-vinylcarbazole) with an efficient Yb3+-centered NIR luminescent complex monomer [Zn(L-1)(4-vinyl-Py)Yb(L-2)(3)] (3) (H2L1 = N,N-bis(salicylidene)cyclohexane-1,2-diamine, 4-vinyl-Py = 4-vinyl-pyridine, and HL2 = (Z)-3-methyl-1-phenyl-4-(2,2,2-trifluoro-1-hydroxyethylidene)-1H-pyrazol-5(4H)-one), the obtained single Zn2+-Yb3+-containing metallopolymer Poly(NVK-co-3) with an additional PVK (poly(N-vinylcarbazole))-to-Yb3+ Foster energy transfer was used as the emitting layer for the realization of NIR PLEDs. Moreover, among the Yb3+-centered NIR PLEDs, the superior performance (irradiances of 80.14-85.63 W cm(-2) and efficiencies of 0.05-0.058%) of the 75:1 feeding devices, the advantages of a low turn-on voltage (5-8 V), and the weak efficiency-roll-off relative to that of the small-molecule organo-Yb3+-based NIR OLEDs render the Yb3+-containing metallopolymer a new platform for PLEDs with wavelength above 900 nm.