In this study, a photocatalyst S-doped WO3 was successfully synthesized by the hydrothermal method. The prepared undoped and S-doped WO3 samples were then characterized by XRD, SEM, XPS, and UV-vis DRS. The results showed that the band gap energy of S-doped WO3 was lower than that of the undoped WO3, which led to a better absorption of visible light. Furthermore, the results of XPS analysis suggested that the doping with S element resulted in an increase in lattice oxygen vacancies on the surface of S-WO3, which could effectively improve the photocatalytic activity. The photocatalytic performance of the S-WO3 samples were evaluated by the measurement of methylene blue (MB) degradation under visible light irradiation. The experimental results demonstrated that S-doped WO3 sample exhibited a much better photodegradation performance compared to undoped WO3, with the maximum MB removal efficiency of 78.7% for the 5% S-WO3 sample. Based on the above results, the mechanisms of photodegradation of MB by S-WO3 were discussed.

中文翻译：

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可见光照射下S掺杂WO3的合成及光催化活性研究。

在这项研究中，水热法成功地合成了光催化剂S掺杂的WO3。然后通过XRD，SEM，XPS和UV-vis DRS对制备的未掺杂和S掺杂的WO3样品进行表征。结果表明，掺S的WO3的带隙能低于未掺WO3的带隙能，可见光吸收更好。XPS分析的结果表明，S元素的掺杂导致S-WO3表面晶格氧空位的增加，可以有效提高光催化活性。通过在可见光照射下测量亚甲基蓝（MB）降解来评估S-WO3样品的光催化性能。实验结果表明，与未掺杂的WO3相比，掺S的WO3样品表现出更好的光降解性能，5％S-WO3样品的最大MB去除效率为78.7％。基于以上结果，讨论了S-WO3对MB的光降解机理。