Synthesis of Ag2S and Ag2Se nanoparticles in self assembled block copolymer micelles and nano-arrays fabrication

This paper describes a simple approach based on self assembled polystyrene-block-poly(4-vinylpyridine) (PS-P4VP) copolymer micelles for the fabrication of ordered 2-dimesional nano-arrays of Ag2S and Ag2Se. The nanoparticles were synthesized directly inside the P4VP micelles core at room temperature and nano-arrays were obtained by spin coating on silicon wafer. High resolution-transmission electron microscopy and powder X-ray diffraction characterization suggests the nanoparticles are crystalline. Higher band gap energy (1.76 eV for Ag2S and 1.35 eV for Ag2Se) compared to their bulk materials obtained from the absorption studies reveals that the nanoparticles are within the quantum confinement regime.