Direct photocurrent generation from nitrogen doped TiO2 electrodes in solid-state dye-sensitized solar cells: Towards optically-active metal oxides for photovoltaic applications

► Demonstration of solid-state dye-sensitized solar cells based on N-doped TiO2. ► Photocurrent increases using the doped electrode compared to pure TiO2. ► The direct charge generation by the doped metal oxide is discussed. ► The influence of N is revealed by numerical simulations based on cluster approach. ► EPR reveals the presence of substitutional N, as well as surface related N.