Hollow spheres of Cu2S nanoparticles with an average diameter of 200-400 nm have been prepared by thermal decomposition of CuSCN spheres at 450 degrees C and reaction with aqueous ammonia. The products were characterized by powder X-ray diffraction, transmission electron microscopy and UV-vis absorption spectroscopy. The band gap is estimated to be 2.96 eV according to the results of optical measurements of the hollow spheres of Cu2S nanoparticles. (C) 2008 Elsevier B. V. All rights reserved.