| Ag3PO4/Ag2S/g-C3N4复合光催化剂的制备与性能 |
| Preparation and Performance of Ag3PO4/Ag2S/g-C3N4 Composite Photocatalyst |
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| 摘要: 通过沉积法和离子交换法成功地制备了Ag3PO4/Ag2S/g-C3N4复合型光催化剂。利用X射线多晶粉末衍射仪（XRD）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）、X射线光电子能谱（XPS）、N2吸附-脱附等温线、紫外-可见漫反射光谱、荧光光谱等手段对样品进行了表征。通过降解罗丹明B考察其可见光催化活性及稳定性，研究了硫化钠与磷酸银物质的量的比值（nNa2S/nAg3PO4）、g-C3N4添加量对所制备复合光催化材料性能的影响，同时对光催化机理进行了探讨。结果表明，随着nNa2S/nAg3PO4的增加，所得复合催化材料活性先增加后降低；当nNa2S/nAg3PO4为1.5%、g-C3N4与Ag3PO4的质量比为3：7时制备的催化剂ASC1.5的光催化活性最好，在可见光照射下，40 min内可将罗丹明B完全降解，且5次循环使用后仍保持较高的催化活性。和Ag3PO4相比，Ag3PO4/Ag2S/g-C3N4复合型光催化材料的活性与稳定性都得到明显提高，这主要归因于复合催化剂比表面积和孔结构的增加，载流子分离效率的提高。光催化机理研究表明，空穴（h+）、超氧阴离子自由基（·O2-）和羟基自由基（·OH）都是光催化过程中的主要活性物种。三者作用大小依次为：h+ > ·O2- > ·OH。 |
| 关键词: Ag3PO4 g-C3N4 Ag2S 光催化 可见光 |
| 基金项目: 国家自然科学基金（No.51572074）和湖北省绿色轻质材料重点实验室开放课题（No.201710A12）资助。 |
| Abstract: Ag3PO4/Ag2S/g-C3N4 composite photocatalysts were successfully prepared by a deposition-ion exchanged combined method. And the obtained samples were characterized by X-ray powder diffractometer (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), N2 adsorption and desorption isotherms, UV-visible diffuse reflectance spectroscopy, fluorescence spectrophotometry and so on. The catalytic activity and stability of the catalysts were evaluated by degradation of rhodamine B under visible light. The effect of molar ratio of sodium sulfide to silver phosphate (nNa2S/nAg3PO4) on the photocatalytic performance of the silver phosphate was studied. In addition, the photocatalytic mechanism was also investigated. The results show that, with the increase of nNa2S/nAg3PO4, the activity of the obtained composite catalytic material increased firstly and then decreased. When nNa2S/nAg3PO4 was 1.5%, the obtained ASC1.5 catalyst could completely degrade rhodamine B within 40 min under visible light irradiation, and also maintained high activity after five-cycle use. Compared with single silver phosphate, the activity and stability of Ag3PO4/Ag2S/g-C3N4 composite photocatalytic materials were significantly improved, which was mainly attributed to the increase of surface area and the presence of porous structure that enhanced separating efficiency of electron-hole pairs. The study of photocatalytic mechanism over the composite catalyst have shown that h+, ·O2- and ·OH were the main active species in the photocatalytic process. The order of the role of the above three species was:h+ > ·O2- > ·OH. |
| Keywords: Ag3PO4 g-C3N4 Ag2S composite catalyst photocatalysis visible light |
| 投稿时间：2019-02-14 修订日期：2019-04-08 |
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| 邓军阳,汪杰,朱思龙,聂龙辉.Ag3PO4/Ag2S/g-C3N4复合光催化剂的制备与性能[J].无机化学学报,2019,35(6):955-964. |
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