A facile synthesis of zinc blende ZnSe nanocrystals

Abstract

Since ZnSe is less toxic than cadmium based materials, ZnSe nanocrystal is a potential candidate for optoelectronic and fluorescent labelling applications. In this paper, colloidal ZnSe nanocrystals are successfully synthesized from zinc stearate and elemental selenium in a paraffin hot-matrix. The method is environment-friendly and of low cost compared with the conventional methods, which are generally toxic and expensive. The nanocrystal-nanocrystal interactions will significantly affect the optical properties and thus a detailed study is desirable. Here, we comprehensively study the interaction through the van der Waals interaction energy, electrostatic energy, steric energy and depletion interaction energy. The corresponding photoluminescence and absorption spectra show obvious excitonic features. Our results show that the nanocrystals can be converted to a water-dispersible system when the dominant emission is still from the excitonic recombination on ZnSe nanocrystals. © 2009 IOP Publishing Ltd.