Ag2S/Ag3PO4/Ni复合薄膜的制备及其光催化性能

采用电化学方法制备Ag_2S/Ag_3PO_4/Ni复合薄膜,以扫描电子显微镜(SEM)、X射线衍射(XRD)、紫外-可见漫反射光谱(UVVis DRS)对薄膜的表面形貌、晶相结构、光谱特性及能带结构进行了表征,以罗丹明B为模拟污染物对薄膜的光催化活性和稳定性进行了测定,采用向溶液中加入活性物种捕获剂的方法对薄膜的光催化机理进行了探索。结果表明:最佳工艺制备的Ag_2S/Ag_3PO_4/Ni是由均匀的球形纳米颗粒构成的薄膜,其光催化活性明显优于纯Ag_3PO_4/Ni薄膜和纯Ag_2S/Ni薄膜,且在保持薄膜光催化活性基本不变的前提下可循环使用6次。提出了可见光下Ag_2S/Ag_3PO_4/Ni复合薄膜光催化降解罗丹明B的反应机理。

Ag2S/Ag3PO4/Ni Thin Films: Preparation and Photocatalytic Activity for Rhodamine B

Ag₂S/Ag₃PO₄/Ni composite thin films were prepared by electrochemical method. The surface morphology, phase structure, optical characteristics and band structure of the thin film were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS), respectively. Its photocatalytic properties and stability were evaluated with rhodamine B (RhB) as a model compound. Using a method of adding active species scavenger to the solution, mechanism of photocatalytic degradation of the film was explored. The results show that the Ag₂S/Ag₃PO₄/Ni thin film is composed of uniform spherical nanoparticles. The photocatalytic activity of the as-prepared Ag₂S/Ag₃PO₄/Ni thin film was higher than those of pure Ag₃PO₄/Ni thin film and Ag₂S/Ni thin film respectively. The film maintains nearly 100% of their corresponding initial photocatalytic activity after 6 cycles. Furthermore, the photodegradation mechanism of the composite films for RhB under the visible light was preliminary proposed.