Preparation of luminescent polyelectrolyte/Cu-doped ZnSe nanoparticle multilayer composite films

ZnSe and Cu-doped ZnSe nanoparticle aqueous suspensions were prepared in th e presence of mercaptopropionic acid (MPA). Cu-doped ZnSe nanoparticles exh ibited a strong blue emission that was strongly dependent upon the Cu dopan t level and the chemical surface passivation produced by zinc-mercaptopropi onic acid complexes. These Cu-doped ZnSe nanoparticles were further assembl ed into ultrathin polymer-supported films using electrostatic interactions and the layer-by-layer assembly method. UV-visible spectroscopy and X-ray p hotoelectron spectroscopy (XPS) provided evidence for the presence and opti cal activity of Cu-doped ZnSe nanoparticles within the polymer ultrathin fi lms. Moreover, XPS data supported the presence of zinc mercaptopropionic ac id complexes on nanoparticle surfaces and the presence of Cu+ ions with hig h luminescent activity in the doped nanoparticles. (C) 2001 Academic Press.