Temperature-Dependent Recombination Processes in Small-Sized PbSe/PbS Core/Shell Colloidal Quantum Dots

  • Diana YANOVER Technion - Israel Institue of Technology
  • Anna RUBIN-BRUSILOVSKI Technion - Israel Institue of Technology
  • Richard ČAPEK Technion - Israel Institue of Technology
  • Aldona SASHCHIUK Technion - Israel Institue of Technology
  • Efrat LIFSHITZ Technion - Israel Institue of Technology
Keywords: small-sized CQDs, PbSe/PbS core/shell, surface oxidation, temperature-dependent PL, and PL dynamics

Abstract

The work focuses on the optical investigation of temperature-dependent recombination processes in small-sized PbSe/PbS core/shell colloidal quantum dots (CQDs) with core diameter of (2 – 2.5) nm and the shell thickness of (0.5 – 1.0) nm under air-free conditions and after air exposure. These CQDs have a tunable absorption edge around 1 μm and a rather narrow photoluminescence linewidth, their emission recombination process is characterized by the μs time-scale and by longer radiative lifetimes in the entire temperature range and especially at low temperatures (a 2.6-fold increase) as compared to the corresponding PbSe samples. The PbSe/PbS core/shell CQDs are oxidation-stable towards time-limited air exposure.

DOI: http://dx.doi.org/10.5755/j01.ms.20.2.6321

Published
2014-06-13
Section
ELECTRONIC AND OPTICAL MATERIALS