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.

中文翻译：

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镧对提高水热法制备TiO2纳米粒子可见光光催化活性的作用

在这项工作中，通过水热法成功合成了具有不同 La 含量的 La 掺杂的 TiO2 (La-TiO2) 纳米粒子，旨在提高可见光光催化性能。通过XRD、BET、TEM、XPS、FT-IR、光催化性能和光电化学分析对所制备的光催化剂进行了表征。实验结果表明，La掺杂可以抑制相变并阻碍TiO2的微晶生长。与其他样品相比，1.5% La-TiO2 在可见光下表现出最高的光催化活性，这归因于更大的比表面积和更好的光生空穴和电子分离能力的协同效应。此外，1.5% La-TiO2 表现出优异的回收性能，