Cadmium quantum dots

Synthesis of CdSe Quantum Dots from Dimethyl Cadmium... 

Although direct synthesis of cadmium chalcogenide quantum dots in the aqueous phase was achieved nearly 30 years ago, the synthesis of size-controlled CdSe quantum dots in the aqueous phase became possible only recently. Rogach et al. successfully synthesized CdSe quantum dots in the aqueous phase from a mixture of cadmium perchlorate (4.7 mmol), sodium hydroselenide (2.2 mmol), and 2-mercaptoethanol or 1-thioglycerol (11.54mmol) [15]. In a typical synthesis, the above mixture was refluxed in an aqueous NaOH solution (pH = 11.2) in a N2... 

Lovric J, Cho SJ, Winnik FM, Maysinger D (2005) Unmodified cadmium telluride quantum dots induce reactive oxygen species formation leading to multiple organelle damage and cell death. Chem Biol 12 1227-1234... 

Surface effects on the properties of cadmium selenide quantum dots were investigated [90]. 

A major concern for the use of these quantum dots in liquid crystal applications is their stability. Weller et al. using NMR spectroscopy, UV-vis spectrophotometry, and analytical ultracentrifugation (AUC) showed that thiol-stabilized cadmium chalcogenide quantum dots are unstable at low particle concentrations (<10 pM in DMF), i.e., even the covalently bound thiols desorb from the quantum dot surface... 

While CdS and CeSe quantum dots are particularly luminescent and have been used extensively, there are concerns over their application in medical imaging in particular because of the potential toxicity associated with cadmium. As a result the syntenthesis of alternative luminescent nanoparticles based on less toxic materials such as Zn3P2 stabilised by tri-/j-octylphosphine oxide is an active area of endeavour.41... 

H. Noglik and W. J. Pietro, Chem. Mater., 7, 1333 (1995). Surface Functionalization of Cadmium Sulfide Quantum Confined Semiconductor Nanoclusters. 2. Formation of a Quantum Dot Condensation Polymer. 

Figure 7.11 A schematic view of kem dependence on quantum dot size in the case of cadmium selenide...

As shown in Fig. 10.3, the fiuorescence quantum yield, monodispersity and photostability of these polymer-coated quantum dots are strongly dependent on the molar capping ratio (MCR), which is calculated by dividing the sum of basic groups (amine or thiol) on the polymer by the sum of cadmium and tellurium atoms on the quantum dot surface. When the MCR values are below 1.0, the amount of polymer is insufficient to completely coat 2.5-nm... 

For biological applications of quantum dots it is important to develop the technology for water soluble highly luminescent cadmium selenide nanocrystals. Obviously, the as-synthesized hydrophobic nanocrystals can not be utilized as fluorescent markers in immunoanalysis since such material must be water compatible [1-2]. 

Cadmium sulfide is a wide band gap semiconductor used for optical applications, like solar cells, lasers, quantum dots, or biological labels [1]. It is well known that semiconductor properties of CdS can be tailored by reducing the size of particles down to the nanometer scale [2]. Since the atomic structure affects greatly semiconductor properties, a study of CdS nanoparticles is performed in this work. 

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