表面负载纳米银的铁电钛酸钡及其光催化性能研究

摘要

采用光沉积法在铁电钛酸钡(BT O)表面负载纳米银粒子,使用XRD、SEM/EDX、T EM和XPS对光催化剂的微观结构进行表征,结果表明随着光沉积时间的延长,纳米银粒子的尺寸与负载量均有所增加.光沉积时间为30s时,表面银粒子的尺寸约为5nm,此时模拟太阳光下光催化降解罗丹明B的效率最高,约为BT O的7.5倍,这主要归因于贵金属的电子陷阱作用和表面等离子共振引起的可见光吸收增强.此外,通过对比OH·捕获剂-乙醇加入前后光催化效率的变化,证明OH·对光降解起主要作用.%Silver nanoparticles were photodeposited onto the surface of ferroelectric barium ti-tanate.The microstructure and photocatalytic properties of the obtained photocatalysts were investigated by using XRD、SEM/EDX、TEM、XPS and UV-Vis spectroscopy.With increas-ing the photodeposition time,the size and amount of surface-loaded silver nanoparticles in-crease as well.The highest photodegradation rate of Rhodamine B was obtained in Ag-BTO-30s,where the silver particle size was roughly 5 nm.Its photodegradation rate was about 7.5 times that of BTO.This improved photocatalytic activity was attributed to the electron-trap roles of noble metal silver and the enhanced absorption in the visible-light range arising from surface plasmon resonance.Finally,the critical role of OH· in photodegradation was verified by the significantly decreased photodegradation after the addition of ethanol which is consid-ered as a O H · scavenger.