Enhanced light extraction and tunable chromaticity in white organic light-emitting devices with ZnO nanopillars

Robust ZnO nanopillars (NPs) with well-controlled morphology were directly prepared on the glass surface of a white organic light-emitting diode (WOLED) substrate using a hydrothermal process. The NPs can effectively recover light loss in the glass substrate and the current efficiency of the device increased by 20%. In addition, the chromaticity coordinates of the WOLED can be tuned by selecting the dimensions of the ZnO NPs. As a consequence, it is possible to produce a solar light spectrum using this technique. Furthermore, the nanotextured glass surface was superhydrophobic, which caused self-cleaning properties to the surface and help maintain maximum light output.