Metal-anode-dependent spectra and efficiency in blue top-emitting organic light-emitting devices

In this study, the blue top-emitting organic light-emitting devices (TEOLEDs) with different metal anodes are fabricated. The effect of different anode materials on the spectra and efficiency of blue TEOLEDs is studied. We demonstrate that Al is a more suitable anode material for blue TEOLEDs due to its larger phase shift on reflectance (PSR) than the other common metal materials, such as Ag and Au. The influence of light outcoupling layer (LOL) on the transmittance and PSR of cathode is also investigated to obtain the optimum condition for devices. Angle-independent electroluminescence (EL) spectra are obtained in blue TEOLEDs for each metal anode but the device with Al anode possesses higher efficiency and much thicker organic layers, which is beneficial to the lifetime of the device. These results offer a practicable platform for the realization of TEOLEDs based full-color displays and lightings.