An upconversion device based on high-performance dual-layer white organic electroluminescent devices

Abstract

Large-area imaging techniques in the short-wave infrared spectral region remain a pressing need. Organic light-emitting diodes and infrared photodetectors can be combined to form a near-infrared (NIR) to visible upconversion device, which has great potential to replace traditional infrared imaging systems. The integration of a white organic light-emitting diode (WOLED) with infrared photodetectors has become essential to realize full-color displays for its simple preparation process and high compatibility. This work has designed and optimized a WOLED to achieve stable emission with high brightness (19 470 cd m−2) and high external quantum efficiency (EQE = 18.08%) at a wide voltage range, thereby reducing chromaticity drift caused by voltage fluctuations. Moreover, photon-generated holes in the NIR-sensitive photodetector are able to inject into the WOLED for visible light emission. Consequently, we have obtained a high-performance upconversion device with a luminance on-off ratio exceeding 5 × 103 at 850 nm NIR and a high color stability over a wide range of operating voltage. Our efforts have accomplished a high-performance upconversion device from NIR to white visible light, laying the groundwork for a preliminary exploration of full-color displays.