Development of InP Quantum Dot-Based Light-Emitting Diodes

High-performance quantum dot light-emitting diodes (QLEDs) are being considered as a next-generation technology for energy efficient solid-state lighting and displays. InP QLEDs are the most promising alternative to the toxic CdSe QLEDs. Unlike the problems of poor hole injection in CdSe-based QLEDs, highly delocalized electrons and parasitic emissions are serious problems in green-emitting InP QLEDs. The loss mechanism and device physics in InP QLEDs have not been sufficiently studied since the first report of InP QLED in 2011. This Focus Review summarizes the recent efforts on improving the performance of InP QLEDs from the perspectives of core/shell structures to optimization of carrier transport layers. It is our intention to conduct a review as well as clarify some previous misunderstandings regarding the device physics in InP QLEDs and to provide some insights for the possible solutions to the challenging problems in InP QLEDs.