Preparation of Er3+:YAlO3/Fe-doped TiO2–ZnO and its application in photocatalytic degradation of dyes under solar light irradiation

In this work, Er3+:YAlO3/Fe-doped TiO2–ZnO composite, a novel photocatalyst, was synthesized by ultrasonic dispersion and liquid boiling method and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Of which, as an upconversion luminescence agent, the Er3+:YAlO3 can transform the visible light in solar energy into ultraviolet light, satisfying the requirement of TiO2–ZnO composite for photocatalytic degradation. The photocatalytic activity of Er3+:YAlO3/Fe-doped TiO2–ZnO composite was evaluated through the degradation of Acid Red B dye under solar light irradiation. The effects of preparation conditions such as Er3+:YAlO3 content, heat-treated temperature and heat-treated time on the photocatalytic activity of Er3+:YAlO3/Fe-doped TiO2–ZnO composite were examined. In addition, the influences of solar light irradiation time, dye initial concentration and Er3+:YAlO3/Fe-doped TiO2–ZnO amount as well as organic dyes on the photocatalytic degradation were also investigated. The experimental results indicated that the Er3+:YAlO3/Fe-doped TiO2–ZnO composite can effectively utilize solar energy to degrade Acid Red B dye and its photocatalytic activity was much superior to that of Fe-doped TiO2–ZnO composite under the same condition.

Research Highlights
► Fe-doped TiO2–ZnO is used in the degradation of organic dyes in combination with solar light.
► Upconversion luminescence agent Er3+:YAlO3 was applied in photocatalytic degradation.
► The photocatalytic activity of Fe-doped TiO2–ZnO is effectively enhanced by doping Er3+:YAlO3.