A paper from the Laboratory of Nano-Bioengineering, NRNU MEPhI, on the optical properties of quantum dots with an unprecedentedly high photoluminescence quantum yield accepted by the JETP Letters

The Russian journal JETP Letters has accepted for publication the paper Optical Properties of Core/Multishell Quantum Dots by P. A. Linkov, P. S. Samokhvalov, K. V. Vokhmintcev, M. Zvaigzne, V. A. Krivenkov, and I. R. Nabiev.

One of the goals of developments in new types of quantum dots is an increased photoluminescence quantum yield. Growing interest in these nanoparticles is determined by permanently arising new developments in photovoltaics, optoelectronics, and biomedicine that call for quantum dots with as bright a photoluminescence as possible.

An increase in quantum yield requires the maximum possible confinement of excited charge carriers within the luminescent cores. Earlier, the authors found that quantum dots with alternating zinc sulfide and cadmium sulfide shells (ZnS/CdS/ZnS) applied onto cadmium selenide cores luminesce more efficiently than traditional quantum dots. The new study continues research on nanoparticles with multilayered shells (so-called multishells), in particular, their optical properties. Robotized methods of layering shells were used to obtain highly size-homogeneous samples of quantum dots with a shell as thick as seven monolayers and a photoluminescence quantum yield close to 100%. In addition, analysis of the photoluminescence life time of these quantum dots has shown there may be an alternative mechanism of emission based on decelerated transfer of the charge carrier from the excited outer layer of the CdS shell to the CdSe core. The study will be published as soon as the second (January) issue of the journal.

This will be the second publication from the Nanochemistry Group of LNBE in the JETP Letters on the properties of core/multishell quantum dots. Earlier this year, a study was published on a high resistance of core/multishell quantum dots to quenching with organic ligands.

The JETP Letters is the English version of the Russian journal Pis'na v ZhETF, one of the most cited Russian physical journals publishing papers on original experimental and theoretical studies.

Contacts:

Pavel A. Linkov, junior researcher (valinkov@gmail.com)

Maria G. Korenkova, LNBE director of external relations (MGKorenkova@mephi.ru)

Laboratory of Nano-Bioengineering, Moscow Engineering Physics Institute
31 Kashirskoe shosse, 115409 Moscow, Russian Federation
http://www.lnbe.mephi.ru/en

 
 
 
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