Abstract
Semiconductor nanocrystals have been expected to be applied in various fields as new fluorescent materials, but one obstacle is that most of these nanocrystals contain cadmium, which is harmful to the human body. In the former reports, highly luminescent ZnSe nanocrystals have been prepared by post-preparative irradiation using ultraviolet lights. Moreover, blue-emitting ZnSe nanocrystals with controlled wavelength had been prepared by adding a slight amount of Cd2+ ions into the solution for synthesis and post-preparative irradiation. In this study, highly luminescent blue-emitting nanocrystals were prepared by adding the Te2- ions into ZnSe nanocrystals. The emission peak wavelength of the nanocrystals can be controlled from 410 to 450 nm, while the photoluminescence efficiency of nanocrystals was increased up to 30%. Furthermore, cadmium-free glass phosphor was prepared by incorporating the prepared nanocrystals into a glass matrix using sol-gel process. The nanocrystals embedded in glass show the same photoluminescent spectra as those in the initial colloidal solution without significant deterioration of photoluminescence efficiency.
