Sahai, Sonal and Husain, Mushahid and Shanker, Virendra and Singh, Nahar and Haranath, D. (2011) Facile synthesis and step by step enhancement of blue photoluminescence from Ag-doped ZnS quantum dots. Journal of Colloid and Interface Science , 357 (2). pp. 379-383. ISSN 0021-9797

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Abstract

Our results pertaining to the step by step enhancement of photoluminescence (PL) intensity from ZnS:Ag,Al quantum dots (QDs) are presented. Initially, these QDs were synthesized using a simple co-precipitation technique involving a surfactant, polyvinylpyrrolidone (PVP), in de-ionised water. It was observed that the blue PL originated from ZnS:Ag,Al QDs was considerably weak and not suitable for any practical display application. Upon UV (365 nm) photolysis, the PL intensity augmented to ∼170% and attained a saturation value after ∼100 min of exposure. This is attributed to the photo-corrosion mechanism exerted by high-flux UV light on ZnS:Ag,Al QDs. Auxiliary enhancement of PL intensity to 250% has been evidenced by subjecting the QDs to high temperatures (200 °C) and pressures (∼120 bars) in a sulphur-rich atmosphere, which is due to the improvement in crystallanity of ZnS QDs. The origin of the bright-blue PL has been discussed. The results were supported by X-ray phase analysis, high-resolution electron microscopy and compositional evaluation.

Item Type:	Article
Additional Information:	Copyright for this article belongs to M/s Elsevier B.V.
Uncontrolled Keywords:	Zinc sulphide; Quantum dot; Photoluminescence; UV photolysis; Hydrothermal method
Subjects:	Chemistry > Physical Chemistry
Divisions:	UNSPECIFIED
Depositing User:	Mr. Abhishek Yadav
Date Deposited:	14 Dec 2012 09:57
Last Modified:	14 Dec 2012 09:57
URI:	http://npl.csircentral.net/id/eprint/905

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