Progress in blue colloidal quantum dots for display applications

Blue quantum dot light-emitting diodes (QLEDs) are key components in developing new generation display technology. To date, the performance of blue QLEDs, particularly the stability, is still far from the commercialization requirements. In this mini-review, we summarize the recent progress in blue-emissive quantum dots (QDs), covering three major material systems: (1) II–VI QDs, including CdSe, CdS, ZnSe, ZnSeTe, CdZnSe, CdZnS, CdSeS, and CdZnSeS; (2) III–V QDs, including InP and GaN; (3) I–III–VI QDs, such as ZnCuGaS, ZnCuInS, and AgInGaS. In addition to size and composition control in type-I core–shell structures, we discuss structural design strategies for blue QDs, encompassing reverse type-I structures such as ZnS/ZnSeTe/ZnS and ZnSe/InP/ZnS, as well as type-II structures including ZnSe/CdS, ZnSe/CdZnS, ZnSe/ZnTe, and ZnSeTe/CdZnSe. Furthermore, we highlight the recent material advancements in blue QLEDs, with a particular focus on their efficiency and stability performance.