Strong microcavity effects in hybrid quantum dot/blue organic light-emitting diodes using Ag based electrode

We investigated the color conversion characteristics of a quantum dot/organic light-emitting diode (QD/OLED) by altering blue emission using the microcavity effect. Compared to the ITO-based OLED, the WO₃/Ag/WO₃ (WAW)-based OLED has a narrow shape of resonance and high cavity enhancement factor. As a result, the peak emission intensity wavelength remarkably shifts as the thickness of the WO₃ layer increases and the WAW-based OLED with inner WO₃ thickness of 120 nm shows an additional emission peak at 420 nm due to the second resonance. As the thickness of the WO₃ layer increases, the color coordinates of the hybrid QD/OLED with the ITO anode are nearly unchanged. However, hybrid WAW-based devices exhibit distinct color coordinates, such as nearly blue light, nearly green light and nearly white light with color coordinates of (0.31, 0.37).