High color rendering index warm white light emitting diodes fabricated from AgInS2/ZnS quantum dot/PVA flexible
Lan Wang1, Xiaojiao Kang2, Daocheng Pan2
1State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, P. R. China. pan@ciac.ac.cn xjkang@ciac.ac.cn and University of the Chinese Academy of Sciences, Beijing, 100049, P. R. China.
Abstract:
Flexible luminescent materials, with the advantages of foldability and crack resistance, have attracted extensive interest owing to their broad application in collapsible optoelectronic devices. In this work, highly luminescent water-soluble green and red AgInS2/ZnS core/shell quantum dots (QDs) are synthesized in an electric pressure cooker. Luminescent and flexible films are fabricated by combining QDs with polyvinyl alcohol (PVA), and the green and red QD/PVA films show a high photoluminescence quantum yield (PLQY) of about 55% and 64% upon 460 nm excitation, respectively. Finally, the green and red QD/PVA films are successfully applied on top of a conventional blue InGaN chip for remote-type warm-white LEDs. As-fabricated warm-white LEDs exhibit a higher color rendering index (CRI) of about 90.2 and a correlated color temperature (CCT) of 3698 K.
