Colloidal Semiconductor Quantum Dot LED Structure and Principles

Colloidal quantum dot light-emitting diodes (QDLEDs) have attracted a lot of attention and have good application prospects due to their excellent luminescence properties (e.g. high color purity) and good stability and solution processability. This chapter reviews the advantages of colloidal quantum dots for display and lighting applications, including color purity, solution processability, stability, and so on. In addition, it introduces the application of semiconductor physics theory to colloidal semiconductor quantum dots from the most basic semiconductor physics concepts. The structure of QDLED devices is sandwich laminated structure, the light-emitting layer is generally located in the center of the device, the common structure of QDLED. The current explanation of the QDLED luminescence mechanism is generally categorized as an injection carrier combination and energy transfer mechanism, where the device is divided into four processes: carrier injection, transport, exciton formation, and combination luminescence under the action of an electric field.