Enhancement of CdSe/ZnS quantum dot-based LED by core-shell modification

In this study, we performed an analysis of quantum-dot-based light-emitting diodes (QD-based LEDs) to investigate the defects at the interface between the core and the shell of the quantum dots (QDs) using gradient-shell QDs (CdSe/Cd1-xZnxSe1-ySy/ZnS, G-QDs) and single-shell QDs (CdSe/ZnS, S-QDs). QDs of the general core-shell type have defects at the core and shell junction interface due to the different lattice constants. However, G-QDs have a low number of lattice defects in the form of a step function between the core and the shell owing to their chemical composition and can more easily confine electron-hole pairs (EHP). Therefore, we fabricated QD-based LEDs by using two emissive layer (G-QDs and S-QDs) and analyzed their characteristics, including their brightness and efficiency.