LAUSR

SrBi2–xLaxNb2O9 ferroelectric powders and ceramics were synthesized by the solid state reaction method, and the effect of La3+ ions doping on the photocatalytic efficiency was investigated. For the low doping rate x (x ≤ 0.02), the leakage current decreases, while the photocurrent and the photocatalytic efficiency increase with x. This is due to the reduction of O-vacancy and the increased spontaneous polarization. For the higher doping rate x (x > 0.02), the leakage current increases with x due to the formation of donorlike LaSr+ state, while the photocurrent and the photocatalytic efficiency decrease with x due to the increased scattering rate by LaSr+, although the spontaneous polarization increases continuously with the La3+ ions doping. These effects indicate that the defects such as LaSr+ impurity states play a more important role for the carrier transport and the photocatalysis. To our best knowledge, it is the first time that the influence of defects on the photocatalytic efficiency of ferroelectric materials is elucidated, and the results of this paper shed light on the search for new ferroelectrics with high photocatalytic performance.SrBi2–xLaxNb2O9 ferroelectric powders and ceramics were synthesized by the solid state reaction method, and the effect of La3+ ions doping on the photocatalytic efficiency was investigated. For the low doping rate x (x ≤ 0.02), the leakage current decreases, while the photocurrent and the photocatalytic efficiency increase with x. This is due to the reduction of O-vacancy and the increased spontaneous polarization. For the higher doping rate x (x > 0.02), the leakage current increases with x due to the formation of donorlike LaSr+ state, while the photocurrent and the photocatalytic efficiency decrease with x due to the increased scattering rate by LaSr+, although the spontaneous polarization increases continuously with the La3+ ions doping. These effects indicate that the defects such as LaSr+ impurity states play a more important role for the carrier transport and the photocatalysis. To our best knowledge, it is the first time that the influence of defects on the photocatalytic efficiency of ferroelectr...