1. A novel two-step controlled basic water phase method for synthesizing size-tunable CdTe/Cd(OH)2 core/shell quantum dots with high quantum yield and excellent stability
- Author
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Cuiping Nie, Beibei Wang, Ma Meihu, Huan Shang, Cai Zhaoxia, and Qi Wang
- Subjects
Chemistry ,Biophysics ,Analytical chemistry ,Shell (structure) ,Fluorescence spectrometry ,Quantum yield ,General Chemistry ,Condensed Matter Physics ,Biochemistry ,Fluorescence ,Atomic and Molecular Physics, and Optics ,Cadmium telluride photovoltaics ,Transmission electron microscopy ,Quantum dot ,Powder diffraction - Abstract
A novel two-step controlled basic water phase method has been developed for synthesizing size-tunable and water-soluble CdTe/Cd(OH) 2 core/shell quantum dots with high quantum yield and good stability. The size of the prepared CdTe/Cd(OH) 2 core/shell quantum dots can be easily manipulated by varying the concentrations of NaOH solution step by step. The maximal emission wavelengths of the series CdTe/Cd(OH) 2 core/shell QDs were from 513 nm to 610 nm (emission colors tuned from green to red). The CdTe/Cd(OH) 2 core/shell quantum dots not only possess high quantum yield (up to 83%) but also exhibit excellent photostability (being stable after being stored for more than 2 months). The CdTe/Cd(OH) 2 core/shell quantum dots were characterized by transmission electron microscopy, high-resolution transmission electron microscopy, X-ray powder diffraction spectrometry, ultraviolet–visible spectrometry and fluorescence spectrometry. The water-soluble nature of the CdTe/Cd(OH) 2 core/shell quantum dots offers great potentiality for their chemical and biological applications. This method is easily controlled, low-cost and reproducible. So it is possible to extend this approach to the preparation of other size-tunable inorganic metal hydroxide capped core/shell quantum dots.
- Published
- 2013