氧空位调控BiVO_(4)纳米片的制备及光解水制氧性能

The Synthesis of Oxygen Vacancy-mediated BiVO_(4) Nanosheets and Their Performance in Photocatalytic Water Splitting O_(2) Evolution

采用水热和烧结方法制备了氧空位调控的BiVO_(4)纳米片。通过X射线衍射仪、电子自旋共振谱仪、透射电子显微镜、紫外-可见分光光度计、荧光光谱仪和光解水制氧系统研究了不同氧空位含量(OV)BiVO_(4)纳米片的结构和光解水制氧性能。通过对氧空位含量的调控,实现了对BiVO_(4)纳米片的光吸收和光电性能的优化,极大提高了BiVO_(4)纳米片的光解水制氧效率。结果表明:引入氧空位后,BiVO_(4)纳米片在可见光区的光吸收明显增强,并且随着氧空位含量的增加,样品的吸收边发生明显红移。适量氧空穴的引入显著提高了光生电子和空穴的分离,从而提高光生电子的利用率。BiVO_(4)-O_(V2)纳米片的光催化产氧速率约433μmol/(h·g),约为BiVO_(4)纳米片的10倍。

Oxygen vacancy-mediated BiVO_(4) nanosheets were synthesized with the hydrothermal and sintering methods.The structure and hydrogen production properties of BiVO_(4) nanosheets with different oxygen vacancy(OV)contents were studied with X-ray diffractometer(XRD),electron spin resonance spectroscopy,high resolution transmission electron microscope,UV-Vis spectrophotometer,fluorescence spectrometer and the photocatalytic O_(2) evolution system.Through the regulation of Ov content,the optical absorption and optoelectronic properties of BiVO_(4) nanosheets were optimized,and the photocatalytic O_(2) production efficiency was greatly improved.The results showed that the optical absorption of BiVO_(4) nanosheets in the visible region was significantly enhanced after OV introduction,and the absorption edge of the sample is obviously red-shifted with the increase of OV content.The introduction of an appropriate OV amount could significantly improve the separation of photogenerated electrons and holes,thus improving the utilization rate of photogenerated electrons.The photocatalytic O_(2) production rate of BiVO_(4)-O_(V2) nanosheets was about 433μmol/(h·g),which was about 10 times higher than that of BiVO_(4).