【摘要】 报道了在含氟的酸性水溶液中,对电沉积制备的WO3薄膜电极进行电化学刻蚀,并采用光电化学、扫描电子显微镜(SEM)、X射线衍射(XRD)、光电子能谱(XPS)、紫外-可见漫反射光谱、光致发光(PL)等方法对电极进行了表征.结果表明,刻蚀使电极比表面积增大,质量减少,重要的是可使电极表面状态发生变化.在相同催化剂质量和比表面积的条件下,这种变化显著提高了WO3薄膜电极在可见光和紫外-可见光照下的光电转换性能.机理研究表明,电极光电化学性能提高可归因于刻蚀使电极表面发生氟化,光生载流子表面复合中心数目减少,平带电位负移.刻蚀对电极的吸光性质和晶体结构等未检测出明显变化.氟化电极在酸性中具有良好的光电化学稳定性.更多还原

【Abstract】 A new and simple method of electrochemical etching in acidic aqueous solutions containing fluorine for the electrodeposited WO3 thin films is presented.The samples were characterized by photoelectrochemistry,scanning electron microscopy(SEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),UV-Vis diffuse reflectance spectroscopy,and photoluminescence(PL).Results showed that the etching increased the specific surface area with a concomitant reduction in the catalyst mass and also a change in the surface status of the electrodes.This modification of the surface status improved the photoelectrochemical performance of the electrodes under visible and UV-Vis light illumination with the same mass and specific surface area.This enhancement can be ascribed to the surface fluorination of the electrodes,which result in a decrease in the surface recombination centers and a negative shift in the flatband potential.The light absorption and crystalline were found to be unchanged by etching.The etched WO3 film electrode shows excellent photoelectrochemical stability in acid solutions.This provides a novel method for increasing thephoton electric conversion efficiency of WO3 thin film electrodes.更多还原