Recharge processes of paramagnetic centers during illumination in nitrogen-doped nanocrystalline titanium dioxide

Nitrogen-doped titanium dioxide (N-TiO2) has been investigated by the EPR-technique. Two types of paramagnetic centers - N-center dot and NO center dot-radicals - were detected in the samples. Both N-center dot and NO center dot-related centers are recharged during illumination. Band diagrams of TiO2 with N-center dot and NO center dot radicals energy level position are proposed. (c) 2015 Elsevier B.V. All rights reserved.