The role of lanthanum in improving the visible-light photocatalytic activity of TiO2 nanoparticles prepared by hydrothermal method

In this work, the La-doped TiO2 (La–TiO2) nanoparticles with different La content were successfully synthesized by hydrothermal method aiming at enhancing the visible-light photocatalytic performance. The as-prepared photocatalysts were characterized by XRD, BET, TEM, XPS, FT-IR, photocatalytic performance and photo-electrochemical analysis. The experimental results indicate that La doping could suppress the phase transformation and hinder the crystallite growth of TiO2. Compared with other samples, the 1.5% La–TiO2 displays the highest photocatalytic activity under visible light, attributing to the synergic effect of the larger specific surface area and better separation capability of photo-generated holes and electrons. In addition, 1.5% La–TiO2 exhibits the outstanding recycling performance, and the degradation efficiency of the fifth day falls by 6.34% compared with the first day.