Study of the electroluminescence performance of NiO-based quantum dot light-emitting diodes: the effect of annealing atmosphere

Abstract NiO is fabricated by a simple solvothermal reaction using tert-butyl alcohol and nickel acetylacetonate as precursors at 200 °C for 20 h. NiO nanocrystals were dispersed in ethanol followed by a spinning coating technique on indium tin oxide (ITO) substrates to form NiO coating as a hole injection layer in quantum dot light-emitting diodes (QLEDs). NiO coating is annealed in ultraviolet ozone, air and nitrogen atmosphere, respectively. NiO coating is analyzed by ways of atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS) and Hall effect measurements. Electroluminescence performance of NiO-based QLEDs is enhanced after ultraviolet ozone treatment due to the increased conductivity of NiO coating.