Growth of Medium-Sized InP Quantum Dots with High Photoluminescence Efficiency and Enhanced Stability

Abstract

This study introduces medium-sized core/shell InP quantum dots (QDs) with high photoluminescence (PL) efficiency and remarkable material stability. The incorporation of a ZnSe interlayer between the core and the thicker outer ZnS shell enhances both the optical performance and material stability. When further increasing the S/Se ratio to synthesize larger QDs with a thicker ZnS layer, optical performance significantly declines despite the improvement in stability. To achieve QDs with superior optical performance and stability, we controlled the S/Se ratio variation during shell growth and examined its impact on the structure, morphology, and size of InP QDs. Our approach resulted in medium-sized InP/ZnSe/ZnS QDs with tunable wavelengths (606-630 nm), PL quantum yields (PLQY) > 90%, full width at half maximum (FWHM) values < 40 nm, and enhanced material stability.Keywords: indium phosphide (InP), quantum dots (QDs), high efficiency and stability, S/Se ratio of shell, medium-size quantum dots, stainless steel reactor Figure 1