PbSe-Based Colloidal Core/Shell Heterostructures for Optoelectronic Applications

Materials

Gary Zaiats¹  Diana Yanover¹  Roman Vaxenburg¹  Jenya Tilchin¹  Aldona Sashchiuk¹  Efrat Lifshitz² 

[1] Schulich Faculty of Chemistry, Russell Berrie Nanotechnology Institute and Solid State Institute, Technion-Israel Institute of Technology, Haifa 32000, Israel;

关键词: PbSe;    PbSe/PbS;    PbSe/CdSe;    colloidal quantum dots;    core/shell;    alloyed quantum dots;    band-gap tunability;    surface oxidation;   

DOI  :  10.3390/ma7117243

来源: mdpi

【 摘 要 】

Lead-based (IV–VI) colloidal quantum dots (QDs) are of widespread scientific and technological interest owing to their size-tunable band-gap energy in the near-infrared optical region. This article reviews the synthesis of PbSe-based heterostructures and their structural and optical investigations at various temperatures. The review focuses on the structures consisting of a PbSe core coated with a PbSe_xS_1–x (0 ≤ x ≤ 1) or CdSe shell. The former-type shells were epitaxially grown on the PbSe core, while the latter-type shells were synthesized using partial cation-exchange. The influence of the QD composition and the ambient conditions, i.e., exposure to oxygen, on the QD optical properties, such as radiative lifetime, Stokes shift, and other temperature-dependent characteristics, was investigated. The study revealed unique properties of core/shell heterostructures of various compositions, which offer the opportunity of fine-tuning the QD electronic structure by changing their architecture. A theoretical model of the QD electronic band structure was developed and correlated with the results of the optical studies. The review also outlines the challenges related to potential applications of colloidal PbSe-based heterostructures.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.