Synthesis of BiFeO₃: Y³⁺ Nanostructure by Sol-gel Method and Their Photocatalytic Activity

Multi-functional ferroelectric materials are the major topic of discussion in recent years. In order to study the photocatalytic property of ferroelectric materials, BiFeO₃ and Bi_1-xY_xFeO₃ nanostructure were prepared by sol-gel method. The crystal structure, morphology, chemical composition and other physiochemical properties of the samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). In addition, the ultraviolet-visible spectrophotometer and photochemical reactions instrument were applied to study the absorption and the photocatalytic property of the samples. The results show that doping of Y³⁺ can reduce the grain size and the forbidden band gap without changing the lattice structure. Also, according to the fitting analysis of XPS narrow spectrum of O 1s, it is found that the content of oxygen vacancies were increased after Y³⁺ doping. The oxygen vacancies can reduce the recombination rate of hole-electron pairs so that the utilization of carriers is improved. Therefore, the doping of Y³⁺ can increase the photocatalytic efficiency of BiFeO₃, and it can be a promising photocatalytic material.