Li-doped ZnO nanostructures for the organic light emitting diode application

Abstract ZnO and Li-doped ZnO nanoparticles have been synthesized by a simple wet chemical method for its potential application in Organic Light Emitting Diodes (OLED). Studies have been undertaken for structural as well as optical properties of ZnO after Li doping with various concentrations. Field Emission Scanning Electron Microscopy indicated the nanodots structure has formed. X-ray Diffraction reveals the pure hexagonal phase of the wurtzite structure. UV–Visible suggested the exciton characteristic at room temperature while Photoluminescence spectra reveal two different regions (ultraviolet and blue). Synthesized materials have been blended with Poly [9, 9-dioctylfluorenyl-2,7-diyl] (PFO) and prototype OLED has been fabricated using these materials as an emissive layer. Electroluminescence spectra show prominent blue emission at 435 nm at 8 V. Current-Voltage (I-V) curve reveal that the turn-on voltages reduce as compared with pristine PFO device.