Abstract
Semiconducting quantum dots are light-emitting nanocrystals that have been flourished as novel kind of fluorescent label for biomedical diagnostics and biomolecular imaging. In comparison to conventional fluorescence probe, quantum dots have exceptional optoelectronic characteristics, narrow and symmetric emission spectra, size-tunable light emission, and wide absorption spectrum that permit the concurrent excitations of numerous fluorescent colors. Furthermore, quantum dots are substantially bright and have high resistance to photo bleaching compared with fluorescent proteins and organic dye. Here, a new family of quantum dots based on Cd1-xWxSe nanocrystals using microwave assisted hydrothermal route has been developed. The X-ray demonstrated the cubic phase of these nanocrystals and the expansion of their lattice dimensions due to the incorporation of W dopant. The TEM inspected the increase of the sizes of the Cd1xWxSe QDs from 3.5 nm to 10.8 nm due to the increase of W dopant. The W dopant caused redshift of the absorption spectra and reduction of the bandgap from 2.54 eV to 2.32 eV. The inclusion of W dopant in the CdSe improved the intensity of luminescence emission by 8 times with narrow bandwidth and quantum yield of 89 %. These auspicious properties pave the way to use the Cd1xWxSe QDs as fluorescent label for biomedical diagnostics and biomolecular imaging.