Study of the preparation and photoelectric property of nanocrystalline Ag ₂S/TiO ₂ heterostructure films

Nanocrystalline TiO ₂ solution was prepared by hydro-thermal treatment at 230°C with Titanium (IV) isopropoxide (C ₁₂H ₂₈O ₄Ti) as precursor solution. Anatase TiO ₂ nanocrystalline films with hierarchical structure were prepared on FTO glass substrates by electro hydrodynamic (EHD) technique and sintered at 450°C. Nanocrystalline Ag ₂S/TiO ₂ heterostructure films were deposited by chemical bath method using the AgNO ₃ solution and Na ₂S solution as the reactants. The crystal structure, morphology and optical property of the film were investigated. The photoelectrochemical cells have been assembled with nanocrystalline Ag ₂S/TiO ₂ heterostructure films as the photoanode. The results indicate that nano-crystalline TiO ₂ films stack with the submicron spherical clusters, submicron and nanometer channels with wide dimension formed among the clusters which can facilitate the solution facilitation and ions adsorption. Ag ₂S nanocrystalline exist in the Ag ₂S/TiO ₂ heterostructure Films within the range of3 to 5nm. UV-vis absorbance spectra verifies the quantum confinement effects of Ag ₂S nanocrystalline. The photoelectrochemical measurement shows the film possesses photoelectric response characteristic and its photoelectric property decays as illumination time prolonging.