Quantum Dot Emission Layer Gradient for Charge Balance and Quenching Control

The emission layer is divided into three distinct emission layers (first, second, and third emission layers) with sequentially decreasing hole mobility. Each emission layer contains quantum dots with different organic ligand contents, creating a gradient structure that segments the charge transport paths while maintaining exciton confinement throughout the layer.

Different regions of the emission layer are assigned different organic ligand contents to optimize local properties. The first emission layer has lower organic ligand content for better charge transport, while subsequent layers have progressively higher content for improved exciton confinement, creating localized optimization throughout the structure.

The emission layer is segmented into three sub-layers with distinct organic ligand contents and hole mobilities. This segmentation allows independent optimization of charge transport and exciton confinement in different regions while maintaining a systematic fabrication approach using sequential deposition or coating methods.

The organic ligand content parameter is systematically varied across the three emission layers, creating a gradient from lower to higher content. This parameter change enables continuous optimization of the balance between charge transport (favored by lower ligand content) and exciton confinement (favored by higher ligand content).