Microwave-Assisted Growth and Characterization of Water-Dispersed CdTe/CdS Core−Shell Nanocrystals with High Photoluminescence

Abstract

A novel microwave-assisted method of growth of high-quality CdTe/CdS core-shell nanocrystals in the aqueous phase is presented in this paper. The photoluminescence quantum yield (PLQY) is greatly enhanced by epitaxial growth of the CdS shell. Under optimum conditions, the PLQY of as-prepared nanocrystals reaches as high as 75% without any post-treatment. Furthermore, these investigations demonstrate that microwave irradiation is tremendously useful for fast epitaxial growth of nanocrystals due to its special characteristics. As a result, the microwave synthesis is sufficiently time-economizing (only five minutes are required) to obtain optimum amounts of CdTe/CdS core-shell nanocrystals in comparison to the conventional illumination method (several days are required). Therefore, this current research not only provides a rapid microwave synthesis for producing highly fluorescent CdTe/CdS core-shell nanocrystals, but also it presents some advantages of the microwave synthesis in comparison to the illumination method.

A nano- and micro- integrated protein chip based on quantum dot probes and a microfluidic network

“…Nearly monodispersed CdTe/CdS core-shell aqQDs were obtained via microwave irradiation as described in our previous work [24]. Briefl y, a CdTe precursor solution was prepared by adding freshly prepared NaHTe solution to N 2 -saturated CdCl 2 solution at pH 8.…”

“…Nevertheless, in order to meet the requirements of biological applications, QDs synthesized in an organic phase have to be transferred to aqueous solution, which is rather complicated and often associated with significant losses of both photoluminescence (PL) quantum yield (QY) and stability [20 22]. In order to avoid these problems, we recently developed a highly efficient program process of microwave irradiation (PPMI) strategy that allows the synthesis of highly fluorescent water-dispersed QDs directly from aqueous solution (aqQDs) [23,24].…”

Simultaneous formation of ferrite nanocrystals and deposition of thin films via a microwave-assisted nonaqueous sol–gel process

“…As a matter of fact, several papers reported the microwaveassisted solution deposition of metal oxides such as indium tin oxide [40], ZnO [41], TiO 2 [42], BaWO 4 [43], or Eu:YVO 4 [44], on conducting glass substrates or silicon. Also core-shell nanoparticles have been prepared in the microwave by coating preformed nanoparticles with another material, e.g., CdTe/CdS [45], or Au@Ag [46].…”

Protein immobilization techniques for microfluidic assays

“…In contrast, the CdTe core/CdS shell QD was prepared in an aqueous phase. 179 The QD was covered with 3-mercaptopropionic acid (MPA) in order to yield a carboxylic-acid functionalized surface. The carboxylic group was later activated with the NHS ester, and then covalently linked to the amine groups of antibodies.…”