Abstract:

The photoelectrochemical behaviors of the mutual modified nanocrystalline Fe 2O 3 and TiO 2 electrodes prepared by different methods (including the mutual doping of metal ions) were studied. With different incident light wavelength, transient photocurrent spectra showed different characteristics. A characteristics of n-type semiconductor appeared in Ti 4+ doped Fe2O3 nanocrystalline electrode; but there was no photoresponse in Fe2O3 coated TiO2 electrodes because of the dismatch of the energy levels of Fe 2O 3 and TiO 2; a characteristics of p n response coexistence appeared in Fe 3+ doped TiO 2 electrode and TiO 2 modified (coated or coupled ) Fe2O3 nanocrystalline electrodes, even the characteristic of p type semiconductor appeared in two special electrodes. All these phenomena can be explained reasonably by the formation of the microzone of p-type semiconductor.

Key words: TiO2-modified Fe2O3 nanocrystalline electrode, Fe2O3-modefied TiO2 nanocrystalline electrode, ransient photocurrent, Characteristic of p-n coexistence