Preparation and visible-light photocatalysis of hollow rock-salt TiO1−xNx nanoparticles

Abstract

A simple method for the preparation of hollow rock-salt TiO1−xNx nanoparticles and their visible-light photocatalytic activities are presented. By thermal annealing of TiO2 nanoparticles under NH3/N2 gas flow at 800 °C, a rock-salt TiO phase was achieved far below its transition temperature to a monoclinic TiO phase (1250 °C). The composition of the nanoparticles was revealed to be Ti0.7(O0.67N0.33)1 by detailed structural and compositional characterizations, and their structural stability was critically determined by the formation of vacancies and the incorporation of N. The hollow rock-salt TiO1−xNx nanoparticles presented efficient visible-light photocatalytic activity, and their origins were discussed.