Facile synthesis of nitrogen self-doped rutile TiO2 nanorods

Abstract

Nitrogen doping is a promising method to enhance the visible light absorption and photo-catalytic activity of TiO₂. A new method is reported for the synthesis of nitrogen self-doped rutile TiO₂ nanorods, along with the formation study of V-shaped N-doped TiO₂ nanorods, using TiN as a precursor and using a hydrothermal method. Our synthesis method gives a facile and easy way to control nitrogen doping in a TiO₂ lattice. Two types of the V-shaped nanorods, with a (101) coherent boundary of either 114.4° or 134.9° inner angle, were observed. The N-doped TiO₂ nanorods exhibit an enhanced visible light absorption and red-shift in band gap in comparison with pure rutile TiO₂ nanopowders. The mechanisms of N doping and the formation of the V-shaped nanorods are analyzed and discussed. The oriented attachment and Ostwald ripening are considered responsible for the formation and growth of the straight and V-shaped N-doped TiO₂ nanorods.