QUANTUM-SIZE EFFECTS IN NANOCRYSTALLINE SEMICONDUCTING TIO2 LAYERS PREPARED BY ANODIC OXIDATIVE HYDROLYSIS OF TICL3

The TiO2 layers prepared by anodic oxidative hydrolysis of TiCl3 on electrically conducting supports (Pt, C, SnO2, etc.) consist of extremely small particles (1-2 nm), partly crosslinked into 2-30-nm big aggregates. Particle size influences the UV absorption spectra, flatband potential, and anodic photocurrent action spectra as expected for size-quantization effects. Upon heating, the particles grew, but if the layer thickness is below ca. 30-100 nm, size effects remain apparent even after annealing at 450-degrees-C.