Inverted Quantum-Dot Light Emitting Diode Using Solution Processed p-Type WO_x Doped PEDOT:PSS and Li Doped ZnO Charge Generation Layer

Quantum dots (QDs) are a promising material for emissive display with low-cost manufacturing and excellent color purity. In this study, we report colloidal quantum-dot light emitting diodes (QLEDs) with an inverted architecture with a solution processed charge generation layer (CGL) of p-type polymer (tungsten oxide doped poly(ethylenedioxythiophene)/polystyrenesulfonate, PEDOT: PSS:WOx) and n-type metal oxide (lithium doped zinc oxide, LZO). The effective charge generation in solution processed p-n junction was confirmed by capacitance-voltage (C-V) and current density-electric field characteristics. It is also demonstrated that the performances of CGL based QLEDs are very similar when various substrates with different work functions are used.