【摘要】 采用离子交换-沉淀法制备了Ag₃PO₄/AgBr/CNTs复合光催化剂。利用X射线衍射仪（XRD）、扫描电镜（SEM）以及紫外-可见漫反射光谱（UV-Vis）等手段对材料的晶型、形貌特征和光吸收特性进行了表征,并以罗丹明B（Rh B）为目标污染物,考察催化剂的光催化活性和稳定性。测试结果表明,当CNTs的质量添加量为3%时,催化剂的催化活性表现最高,光照90min对Rh B的降解效率为100%;经过5次循环使用,对Rh B的降解率仍然保持在90%左右。通过加入不同的牺牲剂,探讨了材料的光催化机理和光催化过程中的活性物种。实验表明,光催化活性的提高是由于Ag₃PO₄/AgBr形成了异质结以及CNTs对光生载流子的高迁移率,同时h+和·O-2是光催化降解过程中的主要活性物种。更多还原

【Abstract】 Ag₃PO₄/AgBr/CNTs composite photocatalyst was synthesized using ion exchange-chemical precipitation method.X-ray powder diffraction（XRD）,scanning electron microscope（SEM）and UV-Vis diffuse reflectance spectra were used to study the phase structures,morphologies and optical properties of samples,respectively.The photocatalytic activity and stability of composite were evaluated by the degradation of Rhodamine B（Rh B）solution under visible light irradiation.The results showed that the photocatalyst exhibited the highest photoactivity when the content of CNTs 3%,the degradation rate of Rh B was 100% under visible light irradiating for 90 min.After recycling for five times,the degradation rate of Rh B maintained 90%.To evaluate the photocatalytic mechanism of photocatalyst and roles of reactive species during photocatalysis,different scavengers were used for Rh B degradation.The results suggested that the heterojunction at the interface between Ag₃PO₄ and AgBr and efficient separation for photogenerated electron-hole pairs of CNTs were crucial for improving the photocatalytic activity,h+and·O-2 played the major roles for Rh B degradation.更多还原