Simultaneous x-ray and visible spectroelectrochemistry of TiO{sub 2} nanocrystalline films.

The mechanism of semiconductor assisted radio- and photocatalysis is based on the principle that particulate semiconductors behave as miniature electrochemical cells driven by radiolytic or photoinduced charge separation. The efficiency of nanoparticulate wide band gap semiconductors is often determined by energy loss pathways such as charge recombination and charge trapping. It is important therefore to understand the complex interplay between structure and electronic properties and how they effect both the lifetime and chemical potential of charge carriers.