Photoelectron transfer in nanocomposite films, layer by layer self-assembled from polycations and anionic semiconductors

Abstract

Publisher Summary This chapter discusses the results, obtained in the laboratories, on the layer-by-layer self-assembly of ordered nanostructured films, composed of cationic poly(diallylmethylammonium chloride), phosphorus (P), and negatively charged solid particles, onto a variety of substrates. Montmorillonite clay platelets (M), thiol, or sodium hexamethaphosphate-stabilized cadmium sulfide (CdS), lead sulfide (PbS), and polyacrylic acid-stabilized titanium dioxide (TiO2) were employed as anionic particles. The self-assembled films were characterized, by cyclic voltammetry, absorption emission and surface plasmon spectroscopy, transmission electron microscopy, and diffraction measurements. The structures of the nanostructured films were shown to depend markedly on the potential that was applied during self-assembly and on the sequence, in which the clay platelets, the CdS, and the TiO2 particles were layered. Furthermore, photocurrent measurements of composite nanostructured films indicated a marked dependence on the sequence, in which the CdS and the TiO2 particles were layered. Self-assembly of the negatively charged surfactant-stabilized CdS, PbS, and TiO2 nanoparticles onto the positive surface of P was greatly facilitated, by strong electrostatic interactions.