Hydrothermal Preparation of Visible‐Light‐Driven N‐Br‐Codoped TiO₂ Photocatalysts

Abstract

Using a facile hydrothermal method, N‐Br‐codoped TiO 2 photocatalyst that had intense absorption in visible region was prepared at low temperature (100 o C), through a direct reaction between nanocrystalline anatase TiO 2 solution and cetyltrimethylammonium bromide (CTAB). The results of X‐ray photoelectron spectroscopy (XPS) showed the existence of N‐Ti‐N, O‐Ti‐N‐R, Ti 3+ (attribute to the doped Br atoms by charge compensation), and TiO x N y species, indicating the successful codoping of N and Br atoms, which were substituted for lattice oxygen without any influence on the crystalline phase of TiO 2 . In contrast to the N‐doped sample, the N‐Br‐codoped TiO 2 photocatalyst could more readily photodegrade methylene blue (MB) under visible‐light irradiation. The visible‐light catalytic activity of thus‐prepared photocatalyst resulted from the synergetic effect of the doped nitrogen and bromine, which not only gave high absorbance in the visible‐light range, but also reduced electron‐hole recombination rate.