The investigation of the surface properties and conductivity distribution of TiOb4s nanocrystalline film using scanning tunneling microscopy : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Technology at Massey University

Abstract

The use of solid-state materials for efficient conversion of sunlight into electricity has long been a goal of inorganic photochemistry. A molecular approach has been to sensitize wide-bandgap oxide semiconductors to visible light with organic and inorganic compounds exhibiting charge-transfer excited states Atomic force microscopy (AFM) and scanning tunneling microscopy (STM) have been demonstrated in this research as powerful tools for surface studies of nanocrystalline TiO2 films, and has been used to characterize the surface properties of TiO2 film used as semiconducting material in dye-sensitized solar cells. The characterization of both the surface morphology and surface electronic properties of the film have been carried out In addition to the usual qualitative analysis of the sample surface based on the topography images, fractal dimension analysis as a measure of surface roughness and fractality has also been applied during the characterization.