Hybrid electrode interface modification enhances OLEDs performance

Highly conductive transparent anodes based on graphene oxide (GO) functional material mixed with poly(3,4-ethylenedioxythiophene)-polystyrene sulfide (PEDOT:PSS) solution were prepared by spin-coating method, and the conductive properties of the anode mixture were further improved by interface treatment. The square resistance of the hybrid film at 36 nm film thickness was 62 Ω/□ and the transmittance at 550 nm was 89%. OLED devices using optimized GO/PEDOT:PSS hybrid films as anodes have lower turn-on voltages and the highest current efficiencies, with a maximum brightness that is 2.37 times that of pure PEDOT:PSS devices and 2.7 times that of ITO devices. Higher transmittance, conductivity, and better highest occupied molecular orbital (HOMO) level matching after hybrid electrode interface treatment contribute to the performance of GO/PEDOT:PSS hybrid anode OLED devices.