Ce和Eu共掺杂的Ce@Eu-Fe_(2)O_(3)-rGO-Bi_(2)WO_(6)复合光催化剂的性能研究

Study on the performance of Ce@Eu-Fe_(2)O_(3)-rGO-Bi_(2)WO_(6) composite photocatalyst co-doped with Ce and Eu

采用一步水热法在无表面活性剂的条件下制备出了不同Ce∶Eu∶Bi比值的Ce@Eu-Fe_(2)O_(3)-rGOBi_(2)WO_(6)(Ce@Eu-F-r-B)光催化剂。将不同光催化剂复合、双元素离子掺杂、GO复合这3种Bi_(2)WO_(6)催化性能改性方法有效地结合在一起。通过X射线衍射仪、扫描电子显微镜、X射线光电子能谱仪、荧光分光光度计、紫外-可见分光光度计等手段系统研究了不同Ce∶Eu∶Bi比值下Ce@Eu-F-r-B样品的形貌、晶体结构、样品表面原子的化学态、光致发光强度和可见光光催化性能及其变化规律。结果表明:随着Ce和Eu含量的变化,Ce@Eu-F-r-B样品中电负性较小的Ce和Eu取代了电负性较大Bi,Bi 4f峰向结合能小的方向发生偏移;吸收波长先红移再转变为蓝移现象,荧光发射强度逐渐减弱,光催化降解速度先增快后逐渐减慢。

Ce@Eu-Fe_(2)O_(3)-rGO-Bi_(2)WO_(6)(Ce@Eu-F-r-B)photocatalyst with the different ratios of Ce∶Eu∶Bi was successfully synthesized by one-step hydrothermal method in the absence of surfactants.The effective combination of three modification methods for BWO catalytic performance,such as combination of different photocatalysts,ion doping of double elements and GO composite,was combined effectively together.The morphology,crystal structure,chemical states of atoms on the surface of the sample,photoluminescence intensity and visible-light photocatalytic performance and their evolution trend of Ce@Eu-F-r-B samples with the different ratios of Ce∶Eu∶Bi were systematically studied using X-ray diffractometer(XRD),scanning electron microscope(FE-SEM),X-ray photoelectron spectroscopy(XPS),photoluminescence spectroscopy(PL),UV-visible spectrophotometer(UV-Vis)and other analytical instruments.With the change of Ce and Eu content in the samples of Ce@Eu-F-r-B,the less electronegative Ce ions and Eu ions replaced the more electronegative Bi ions,it made the peaks of Bi 4fmoved slightly in the direction of smaller binding energy.The absorption wavelength firstly undergoed a red shift and then changed to a blue shift,PL emission intensities weakened gradually,and its visible light photocatalytic activity first increased and then decreased.