Grain Boundary Controlled Electron Mobility in Polycrystalline Titanium Dioxide

Grain boundaries are shown to play a critical role in controlling electron mobility in nanocrystalline titanium dioxide affecting material performance for applications such as solar energy generation and catalysis. Theoretical modelling demonstrates that electron mobility can be reduced by several orders of magnitude as a result of enhanced electron trapping at grain boundaries and that electron mobility can be improved at high current densities as a result of a highly nonlinear trap filling effect.