Abstract The double heterojunction of Pr2Sn2O7@Bi2Sn2O7/TiO2 composite was prepared by one-step hydrothermal method using TiO2 electrospun nanofibers as substrate. The structures were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, ultraviolet (UV)-visible diffuse reflectance spectroscopy and photoluminescence. The performance of photocatalytic hydrogen production over the composite catalyst was studied under UV–visible light. The Pr2Sn2O7@Bi2Sn2O7/TiO2 composite nanofibers showed high photocatalytic activity for hydrogen production. The hydrogen production rate reached 587.1 μmol h−1 g−1, which was 2.7 and 7.1 times that of Bi2Sn2O7/TiO2 and TiO2, respectively. The main reasons for the high photocatalytic activity included broadened spectral range, 4f–4f transition from Pr3+ of Pr2Sn2O7 and increased separation of the photogenerated carriers by double heterojunction via direct Z-scheme transfer.

中文翻译：

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用于制氢的 Pr2Sn2O7@Bi2Sn2O7/TiO2 双异质结的开发

摘要 以TiO2电纺纳米纤维为基材，通过一步水热法制备了Pr2Sn2O7@Bi2Sn2O7/TiO2复合材料的双异质结。通过 X 射线衍射、扫描电子显微镜、透射电子显微镜、X 射线光电子能谱、紫外 (UV)-可见漫反射光谱和光致发光对结构进行了表征。在紫外-可见光下研究了复合催化剂上光催化制氢的性能。Pr2Sn2O7@Bi2Sn2O7/TiO2复合纳米纤维对制氢表现出很高的光催化活性。制氢速率达到587.1 μmol h-1 g-1，分别是Bi2Sn2O7/TiO2和TiO2的2.7倍和7.1倍。高光催化活性的主要原因包括拓宽的光谱范围，