Abstract:

Rod-shaped Bi₂S₃-modified TiO₂ nanocone (TNCs) photoanode materials were successfully prepared using a two-step hydrothermal method, which explored the optimal loading by adjusting the sulfur content and were used to simulate the degrading oxytetracycline in visible light. The crystalline shape, elemental valence, surface morphology, and photoelectric and electrochemical properties of Bi₂S₃/TNCs photoanodes were characterized in detail. The results found that the photoanodes of Bi₂S₃/TNCs significantly improved the photoelectrocatalytic performance and exhibited lower charge transfer resistance. The photocurrent density was about three times higher than that of TNCs. The test results of UV-vis spectrophotometer at 355nm indicated that the Bi₂S₃/TNCs photoanode successfully degraded 80.3% oxytetracycline within 90 minutes and maintained good stability after 5 cycles. In addition, a possible photoelectric catalytic degradation mechanism was proposed for the experimental analysis of band gap energy, valence band spectrum, Mott-Schottky curve and radical trapping. These results showed that Bi₂S₃/TNCs photoanode had great potential for degrading antibiotics.

Key words: Bi₂S₃/TiO₂ nanocone, photoelectrocatalysis, hygromycin, visible light

摘要：

使用两步水热法成功制备了棒状Bi₂S₃修饰的TiO₂纳米锥（TNCs）光阳极材料，通过调节硫元素的含量探索最佳负载，并用于模拟可见光下降解土霉素。对Bi₂S₃/TNCs光阳极的晶型、元素价态、表面形貌和光电、电化学性能进行了详细的表征。结果表明，Bi₂S₃/TNCs光阳极显著提高了光电催化性能，表现出更低的电荷转移电阻，光电流密度是TNCs的3倍左右。紫外-可见分光光度计在355nm处测试结果表明，Bi₂S₃/TNCs光阳极在90min内成功降解了80.3%的土霉素，5次循环后仍保持良好的稳定性。此外，还对带隙能、价带谱、莫特-肖特基曲线和自由基捕获实验进行分析，提出了一种可能的光电催化降解机理。这些结果表明，Bi₂S₃/TNCs光阳极对降解抗生素具有很大的潜力。

关键词: Bi₂S₃/TiO₂纳米锥, 光电催化, 土霉素, 可见光