Effect of Electron-Electron Interaction on Transport in Dye-Sensitized Nanocrystalline TiO2

摘要

Experimental measurements and continuous-time random walk simulations on sensitized electrolyte-infused porous nanocrystalline TiO(sub 2) films show that the actual electronic charge in the films is significantly larger than that estimated from small-perturbation methods by a constant, light-intensity- independent factor. This observation can be explained by small-perturbation techniques measuring the chemical diffusion coefficient of electrons instead of the normally assumed tracer diffusion coefficient of electrons. The difference between the two diffusion coefficients is attributed to the presence of an exponential density of states through which electrons interact. At high light intensities, an additional extra component owing to Coulomb interactions between the electrons is expected to arise.