Process-Dependent Photocatalytic Properties of Polymer Thin Films Containing TiO2 Nanoparticles: Dip vs Spin Self-Assembly Methods

Abstract

Thin films consisting of polyelectrolytes and positively charged TiO2 nanoparticles were fabricated by the dip and the spin self-assembly (SA) methods. Employing the same deposition sequence in both methods, both SA films showed a similar thickness. We observed a comparatively layered structure in the spin SA film and a fuzzy structure in the dip SA film. As the number of TiO2 nanoparticle layers was increased, the photooxidized amount of iodide and methyl orange increased in the dip SA film but not in the spin SA film due to the limited diffusion of molecules caused by its compact structure.