Influence of the Shell Thickness and Ratio Between Core Elements on Photostability of the CdTe/CdS Core/Shell Quantum Dots Embedded in a Polymer Matrix.
This paper reports a study of photooxidation and photomodification processes of the CdTe/CdS quantum dots embedded in a polymer matrix under ambient condition. During the first few minutes of irradiation, the quasi-inverse increase in photoluminescence intensity has been observed indicating the passivation of the nanocrystal surface traps by water molecules. A prolonged irradiation of the polymer film containing CdTe/CdS quantum dots leads to a significant decrease in the photoluminescence intensity together with the "blue shift" of the photoluminescence peak energy associated with quantum dot photooxidation. The mechanisms of the CdTe/CdS core/shell quantum dot photooxidation and photomodification in a polymer matrix are discussed. We have found a correlation between the photostability of the quantum dots and the CdS shell thickness as well as the ratio of core elements.
Department of Inorganic Chemistry of Solid State and Nanomaterials, Yuriy Fedkovych Chernivtsi National University, Kotsiubynskyi St, 2, Chernivtsi, 58012, Ukraine.
Nataliia
N
Doskaliuk
Department of Inorganic Chemistry of Solid State and Nanomaterials, Yuriy Fedkovych Chernivtsi National University, Kotsiubynskyi St, 2, Chernivtsi, 58012, Ukraine. y.khalavka@chnu.edu.ua.
Yuriy
Y
Khalavka
Department of Inorganic Chemistry of Solid State and Nanomaterials, Yuriy Fedkovych Chernivtsi National University, Kotsiubynskyi St, 2, Chernivtsi, 58012, Ukraine.
Petro
P
Fochuk
Core/shell nanocrystals; Layer-by-layer films; Photoluminescence; Photooxidation; Quantum dots