Synthesis of monodispersed CdS nanoballs through γ-irradiation route and building core–shell structure CdS@SiO2

Monodispersed CdS nanoballs were synthesized through γ-irradiating CdCl2, Na2S2O3 and polyvinylpyrrolidone aqueous solution at room temperature. With these well monodispersed CdS nanoballs, CdS@SiO2 core–shell structures were prepared under hydrolysis of tetraethylorthosilicate without adding a coupling agent. Field emission scanning electron micrograph, transmission electron microscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy, ultraviolet absorption and photoluminescence spectroscopy were used to characterize the products. It is hoped that the core–shell CdS@SiO2 nanoballs would be used as good luminescence detecting material for biological systems, so this may stimulate technological interest and prospect many other applications in materials related fields.