Science News: 2021 Adv. Mater., High efficiency EQE 28.1%! PeLED Synergistic Dual-Additive Strategy
In September 2021, Advanced Materials (IF 30.849) journal published a study. Compared with 3D perovskite, quasi-2D perovskite has long been considered to have a good “energy funnel/cascade” structures and excellent optical properties. Although most quasi-2D perovskite light-emitting diodes (PeLEDs) exhibit high external quantum efficiency (EQE), the Auger recombination caused by high current density will make unsatisfactory operating stability.
The author here uses 18-crown-6 and poly (ethylene glycol) methyl ether acrylate (MPEG-MAA) as the additives and adopts a synergistic dual-additive strategy to produce perovskite films with low defect density and high environmental stability . Because the dual additives containing C-O-C bonds can not only effectively reduce the perovskite defects, but also destroy the self-aggregation of organic ligands, and induce the formation of perovskite nanocrystals with a quasi-core/shell structure. After thermal annealing, MPEG-MAA with its C-C bond can be polymerized to obtain a comb-like polymer, which further protects the passivated perovskite nanocrystals from the influence of water and oxygen.
Through experiments with quantum efficiency measurement and other instruments, it was found that state-of-the-art green PeLED has a normal EQE of 25.2% and a maximum EQE of 28.1%, and its device lifetime (T50) is increased over 10 times in air environment. Above, a novel and effective strategy is provided to make PeLEDs with high efficiency and long service life.
In experiments with instruments such as Quantum Efficiency Measurement.
In experiments with instruments such as Quantum Efficiency Measurement.
Key Word: Quantum Efficiency、perovskite
Article link: https://onlinelibrary.wiley.com/doi/10.1002/adma.202103268