In this work, Ag/WO₃/g-C₃N₄ (AWC) nanocomposites were successfully prepared via a hydrothermal method. Oxytetracycline hydrochloride (OTC) was used to evaluate the photocatalytic activity of the photocatalysts under visible light. The samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectra (Raman), scanning electron microscope (SEM), Ultraviolet–visible spectroscopy (UV–vis DRS), photocurrent density (I-t) and electrochemical impedance spectra (EIS). The results showed that WO₃ and Ag nanoparticles were coupled with g-C₃N₄ successfully. Comparing with pure WO₃ or g-C₃N₄, the visible light absorption region of AWC composites was effectively broadened. The photocatalytic performance experiment illustrated that AWC-2 composite had the highest photocatalytic activity, and 97.74% of OTC (10 mg/L) was degraded in 60 min with 0.4 g/L of AWC-2. The radical scavenging experiments indicated that the superoxide radical (•O₂⁻) and hydroxyl radical (•OH) were the most important active species for OTC oxidation. The five cycle photocatalysis experiment further proved that AWC is a stable photocatalyst for degradation of OTC. Finally, the possible degradation mechanism of Z-scheme heterostructure photocatalysis was proposed according to the experimental results.

在这项工作中，通过水热法成功制备了Ag/WO ₃ /gC ₃ N ₄ (AWC) 纳米复合材料。土霉素盐酸盐（OTC）用于评估光催化剂在可见光下的光催化活性。样品通过 X 射线衍射 (XRD)、X 射线光电子能谱 (XPS)、拉曼光谱 (Raman)、扫描电子显微镜 (SEM)、紫外-可见光谱 (UV-vis DRS)、光电流密度 (It ) 和电化学阻抗谱 (EIS)。结果表明WO ₃和Ag纳米颗粒与gC ₃ N ₄成功偶联。与纯 WO ₃或 gC ₃ N 比较_{如图4所示}，AWC复合材料的可见光吸收区域有效拓宽。光催化性能实验表明，AWC-2复合材料具有最高的光催化活性，0.4 g/L的AWC-2在60 min内降解97.74%的OTC（10 mg/L）。自由基清除实验表明，超氧自由基（•O ₂ ^-）和羟基自由基（•OH）是OTC氧化最重要的活性物质。五循环光催化实验进一步证明了AWC是一种稳定的降解OTC的光催化剂。最后，根据实验结果提出了Z-scheme异质结构光催化可能的降解机制。