An Optically Flat Conductive Outcoupler Using Core/Shell Ag/ZnO Nanochurros |
| |
Authors: | Young Zo Yoo Jin‐Young Na Yoon Soo Choi Yeong Jin Lim Ji‐Hyun Kim Young‐Bin Kim Jae‐Ho Kim Sun‐Kyung Kim Tae‐Yeon Seong |
| |
Affiliation: | 1. R&D Center, DUKSAN Hi‐Metal Co. Ltd, Ulsan, Republic of Korea;2. Department of Applied Physics, Kyung Hee University, Gyeonggi‐do, Republic of Korea;3. Department of Materials Science and Engineering, Korea University, Seoul, Republic of Korea |
| |
Abstract: | Transparent conductive electrodes (TCEs) featuring a smooth surface are indispensable for preserving pristine electrical characteristics in optoelectronic and transparent electronic devices. For high‐efficiency organic light emitting diodes (OLEDs), a high outcoupling efficiency, which is crucial, is only achieved by incorporating a wavelength‐scale undulating surface into a TCE layer, but this inevitably degrades device performance. Here, an optically flat, high‐conductivity TCE composed of core/shell Ag/ZnO nanochurros (NCs) is reported embedded within a resin film on a polyethylene terephthalate substrate, simultaneously serving as an efficient outcoupler and a flexible substrate. The ZnO NCs are epitaxially grown on the {100} planes of a pentagonal Ag core and the length of ZnO shells is precisely controlled by the exposure time of Xe lamp. Unlike Ag nanowires films, the Ag/ZnO NCs films markedly boost the optical tunneling of light. Green‐emitting OLEDs (2.78 × 3.5 mm2) fabricated with the Ag/ZnO TCE exhibit an 86% higher power efficiency at 1000 cd m?2 than ones with an Sn‐doped indium oxide TCE. A full‐vectorial electromagnetic simulation suggests the suppression of plasmonic absorption losses within their Ag cores. These results provide a feasibility of multifunctional TCEs with synthetically controlled core/shell nanomaterials toward the development of high‐efficiency LED and solar cell devices. |
| |
Keywords: | core/shell Ag/ZnO nanochurros optical tunneling organic light‐emitting diodes selective‐facet growth transparent electrodes |
|
|