One-Step Synthesis of High-Quality Water-Soluble CdSe Quantum Dots Capped byN-Acetyl-L-cysteineviaHydrothermal Method and Their Characterization

Abstract

Novel water-soluble CdSe quantum dots (QDs) have been prepared withN-acetyl-L-cysteine as new stabilizer through a one-step hydrothermal route. The influence of experimental conditions, including reaction time, molar ratio of reactants, and pH value, on the luminescent properties of the obtained CdSe QDs has been systematically investigated. The characterization of as-prepared QDs was carried out through different methods. In particular, we realized qualitative and semiquantitative studies on CdSe QDs through X-ray photoelectron spectroscopy and electron diffraction spectroscopy. The results show that the as-prepared CdSe QDs exhibit a high quantum yield (up to 26.7%), high stability, and monodispersity and might be widely used in biochemical detection and biochemical research.

ФОТОЛЮМІНЕСЦЕНЦІЯ НАНОЧАСТИНОК CdSe:Ni ОТРИМАНИХ ХІМІЧНИМ МЕТОДОМ

“…This allows us to assume that transitions involving excitons are responsible for these lines. Lines of a similar nature were observed earlier in [2].…”

“…Colloidal CdSe nanocrystals can be used to create structures emitting in the entire visible light range, as a sensitizer for photopolymer cells and in biomedical visualization [1][2][3][4][5][6][7]. In comparison with organic fluorophores semiconductor nanocrystals are much more stable to photodegradation.…”

A guide to small fluorescent probes for single-molecule biophysics

“…We note that on comparison to core-type CdTe QDs, core shell CdSe/ZnS particles exhibit narrower emission features (Figure 6), though the precise range over which emission occurs and the spectral properties ultimately depend on the materials used, surface coatings and particle size. Though CdTe and CdSe are among the most widely used of all QDs, the implications of the Cd/Te and Cd/Se molar ratios on optical properties such as emission intensity, quantum yield and lifetime is a relatively new area that demands further exploration (163,164) . Nevertheless, their high quantum yields (20-80 %) place them among the brightest of all available probes (165) .…”

Applications of functionalized nanomaterials in photodynamic therapy

“…These QDs emanate from precursors consisting of heavy metal salts that are easily dissolved in water such as chlorides, nitrates and acetates. Capping agents often used for the synthesis of water soluble QDs are small organic molecules such as those containing mercapto-acid (Dhar 2014), mercapto-amine (Zhou et al 2011) and mercapto-amine-carboxylic acid functional groups (Wei et al 2014).…”