Abstract
Cadmium sulfide (CdS) quantum dots (QDs), capped with cetyltrimethylammonium bromide (CTAB), and was synthesized as stable, aqueous, colloidal nanofluid. A series of nine intense, well-resolved emission lines between 400 and 750 nm were observed for the first time when exciting the CdS QDs nanofluid with a 355-nm high energy pulsed Nd:YAG laser radiation. The energy separation between any two successive emission lines equals to the characteristic overtone energy of 295 cm-1 of the longitudinal optical phonon of CdS QDs. In addition, recording the PL spectrum by using a xenon broad band light source resulted in the observation of this characteristic overtone energy of 295 cm-1. In agreement with this photoluminescence characteristic, Raman spectrum exhibited four prominent Stokes lines with Raman shift equal to and multiple of 295 cm-1. Transmission electron microscopy investigation showed that the CdS QDs were spherical with hexagonal wurtzite structure and had a size in the range of 5-10 nm.
Original language | English |
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Pages (from-to) | 3835-3842 |
Number of pages | 8 |
Journal | Journal of Nanoparticle Research |
Volume | 13 |
Issue number | 9 |
DOIs | |
State | Published - Sep 2011 |
Keywords
- Laser-induced photoluminescence
- Nano material synthesis
- Optical characterization
- Optical phonons
- Quantum dots
ASJC Scopus subject areas
- General Chemistry
- Condensed Matter Physics
- Bioengineering
- Atomic and Molecular Physics, and Optics
- General Materials Science
- Modeling and Simulation