The enhanced photocatalytic activity of Yb3+-Ho3+/Er3+ co-doped 3D BiOCl flower

A series of characteristic 3D flower-like BiOCl photocatalysts constructed by the self-assembling of BiOCl nanosheets substructures were synthesized through hydrothermal method, in which Ho3+/Yb3+ and Er3+/Yb3+ ion pairs were introduced to co-dope BiOCl to enhance photo-catalytic activity. Their structure, shape and morphology were not only characterized by power X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM) and transmission electron microscopy (TEM), but also calculated the host electronic structure. The photocatalytic performances of Ho3+/Yb3+ and Er3+/Yb3+ co-doped BiOCl samples were enhanced greatly and evaluated by the degradation of rhodamine B (RhB) in aqueous solutions under the irradiation of stimulated sunlight and 450 nm blue light. To understand the potential reason, optical properties of the as-synthesized BiOCl samples were characterized by UV-vis diffuse reflectance spectra, up-conversion (UC) and down-conversion (DC) luminescence spectra were also investigated. The possible photo-catalytic mechanism was also raised, which develops a feasible method to improve the photocatalytic activity by combining with luminescence.