Advances, Challenges, and Perspectives for Heavy-Metal-Free Blue-Emitting Indium Phosphide Quantum Dot Light-Emitting Diodes

摘要

Quantum dot light-emitting diodes (QLEDs), regarded as promising candidatesin the next-generation display, have attracted much attention recently.In spite of the outstanding performance of cadmium-based (Cd-based)QLEDs, the toxicity of Cd hinders their wide application. Indium phosphidequantum dots (InP QDs) with heavy-metal-free feature and competitive performanceare considered to be able to replace Cd-based QDs as emitting layerin the QLEDs. Much progress is obtained in the red-emitting and green-emittingInP-based QLEDs. However, the blue-emitting ones are faced with greatchallenges and are demanded on full-color display urgently, which is limitedby the inferior performance of blue-emitting InP QDs and lack of investigationsabout their QLED devices. In this review, the encountered challengesfor high-quality blue-emitting InP QDs are presented. Common strategiesfor blue-emitting InP QDs, including size engineering, composition engineering,and surface engineering are presented and analyzed. The progressof blue-emitting InP-based QLEDs, which strongly relies on the advances ofmaterials, is also summarized. Finally, some perspectives from device physicsare provided and discussed to inspire more efficient strategies toward blueemittingInP-based QLEDs.