CdSe nanoparticles, production

We have reported a simple, green, bench top, economical and environmentally benign room temperature synthesis of MSe (M=Cd or Zn) nanoparticles using starch, PVA and PVP as passivating agents. The whole process is a redox reaction with selenium acting as the oxidant and MSe as the reduction product. An entire "green" chemistry was explored in this synthetic procedure and it is reproducible. The optical spectroscopy showed that all the particles are blue shifted from the bulk band gap clearly due to quantum confinement. Starch capped CdSe nanoparticles showed the presence of monodispersed spherical... 

In conclusion, we have successfully demonstrated that, by using a fluorous label and a fluorous solvent, we can affect the phase transfer of gold and CdSe nanoparticles from an aqueous or hydrocarbon medium to the fluorous phase. Single-walled carbon nanotubes and ZnO nanorods can be solubilized in a fluorous solvent after interaction with a fluorous amine. Phase transfer of the nanostructures to a fluorous solvent represents solubilization in a highly nonpolar solvent, accompanied by purification. The high nonpolarity of the fluorocarbon makes it possible to study the optical and other properties of nanostructures in a medium of very low refractive index. Since the fluorocarbon extracts only the species attached to the fluorous label, the process enables one to obtain solely one product in the pure state. We believe that fluorous chemistry may have practical utility in carrying out studies of nanostructures. 

Among the alternate methods, solvothermal decomposition has been very attractive for the production of high quality CdSe QD at a relatively lower temperature. The synthesis procedure employs low cost and less toxic materials and importantly, it avoids the use of inert atmosphere. The two-pot solvothermal approach has many advantages compared with the one-pot synthesis procedures [184]. Major synthetic routes used for the synthesis of CdSe nanoparticles along with the particle size and the capping agent used are summarized in Table 1. 

Fluorescent and photoluminescent nanofiUers, such as CdTe, CdSe, CdS nanoparticles or quantum dots (QDs), ZnS and ZnSe QDs, and complexes of trivalent europium ion (Eu ), are promising inorganic materials with photoelectric, thermoelectric, and photoluminescent properties that find applications in optoelectronic devices, optical sensors, as photocatalysts for organic pollutants remediation [39] or hydrogen production [40], and as fluorescent biomaterials [41]. 

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