Precursor Reactivity-Controlled Synthesis of ZnSeTeS/ZnSe/ZnS Alloy Quantum Dots with High-Color-Purity and Photolithographic Patterning

Environmentally friendly ZnSeTe QDs are attractive candidates for next-generation display and lighting due to their excellent luminescence and composition tunability. However, the substantial reactivity disparity between Se and Te precursors often leads to inhomogeneous Te distribution within ZnSeTe QDs, limiting the color purity and luminescence stability. To overcome these challenges, we developed ZnSeTeS/ZnSe/ZnS gradient alloy QDs to alleviate lattice mismatch and reduce defects, improving the stability and color purity of QDs. The optimized green-emitting QDs exhibit a narrow size distribution (∼5.6 nm), a full width at half maximum (FWHM) of 33 nm, and a photoluminescence (PL) peak at 532 nm, closely approaching the green primary defined by the BT.2020 standard. By adjusting the Te and S incorporation ratios, the PL peaks of the QDs are widely tuned from 420 to 670 nm. Furthermore, through the combination of thiol-ligand exchange and UV lithography, high-precision patterning of the ZnSeTeS/ZnSe/ZnS QDs was achieved with a single pixel size of 20 µm × 20 µm × 2.5 µm, demonstrating broad application prospects in next-generation microdisplay applications such as AR/VR.