Significance of Small-Sized PbSe/PbS Core/Shell Colloidal Quantum Dots for Optoelectronic Applications

Abstract

Small-sized colloidal quantum dots (QDs) consisting of IV–VI semiconductors with the PbSe/PbS core/shell structure were synthesized by a specially developed wet-chemistry method. Their electronic properties were determined by the comparison of theoretical calculations with continuous-wave and transient photoluminescence measurements conducted at various temperatures. The results revealed the formation of quantum dots characterized by a tunable band gap around 1 μm, lifetime exceeding 4.0 μs at room temperature, photoluminescence quantum yield >60%, and resistance to oxidation for a relatively long period of time. The properties of the QDs vary with the core/shell architecture, which is beneficial for their optoelectronic applications.