Fabrication of highly flexible, inverted, indium tin oxide (ITO)-free top-emitting quantum-dot light-emitting diodes (QDLEDs) on elastic polyurethane (PU) substrates is reported here. To cope with the irregular surfaces of the PU substrate, polyvinyl alcohol (PVA) is used as a buffer layer. By adopting the PVA buffer layer, we demonstrate red-color and green-color top-emitting QDLEDs that show turn-on voltages from 4.0 V to 4.5 V, and maximum luminance values of 1200 cd m−2 (red) and 4800 cd m−2 (green). In addition, when the QDLEDs are stuck on the curved surfaces (vials and a tumbler), the devices still exhibit a clear light emission. These highly flexible QDLEDs can pave the way for further development of next-generation wearable or attachable displays, or solid-state lighting.
Bibliographical noteFunding Information:
W. K. Choi and D. K. Hwang appreciate the financial support from the KIST Institution Program (program No. 2E27150 and 2E27160). This research was also supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (NRF-2015R1C1A1A01051841) and by the Technology Development Program to Solve Climate Changes of the NRF funded by the Ministry of Science, ICT & Future Planning (NRF-2016M1A2A2940912) (J. W. Shim). We thank JIN HEUNG IND CO., LTD for supplying PU substrates.
All Science Journal Classification (ASJC) codes
- Materials Chemistry