Highly luminescent thin films from alternating deposition of CdTe nanoparticles and polycations

Thin polymeric films with high concentration of CdTe-nanocrystals are obtai ned by the self-assembly process of layer-by-layer deposition. Water solubl e CdTe particles stabilized by a shell of thioglycolic acid are combined wi th three different polyelectrolytes: poly(ethylenimine) (PEI), poly(allylam ine hydrochloride) (PAH), and poly(diallyldimethylammonium chloride) (PDDA) . The film build-up is monitored by means of absorption and fluorescence sp ectroscopy. The electrostatic adsorption of the particle at the polymer sur face is strongly determined by the pH value of the particle solution and th e chemical structure of the polymer. Polycations with partially unsaturated nitrogen groups exert strong quenching on the particle fluorescence. (C) 1 999 Elsevier Science S.A. All rights reserved.