In this paper, a novel BiOCl/TiO₂ hierarchical composite was successfully synthesized by a facile one-pot solvothermal synthesis with the aid of polyvinylpyrrolidone (PVP). Then, the as-prepared composite was characterized by field-emitting scanning electron microscope (FESEM), transmission electron microscopy (TEM), N₂ adsorption/desorption, X-ray power diffraction (XRD) analysis, X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance spectra (DRS) and electrochemical impedance spectroscopy (EIS), respectively. Research shows that this novel composite exhibits superior visible-light response, enhanced photoactivity and photostability for the formation of the BiOCl/TiO₂ heterojunctions. Especially, the rate constant of the photocatalyst with the molar ratio of anatase TiO₂ about 30% for decomposing RhB, can reach about 0.1510min⁻¹, is far superior to commercial P25, as-prepared anatase TiO₂ nanoparticles and tetragonal BiOCl alone. In addition, the superoxide radicals (O²⁻) and photogenerated holes (h⁺) were demonstrated to be the main active radicals in this photodegradation process. This study further reveals that the enhanced photoactivity of this photocatalyst should be ascribed to the successful formation of BiOCl/TiO₂ heterojunctions and the rapid migration of the interface charges.

中文翻译：

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新型BiOCl / TiO2分层复合材料：合成，表征及在光催化中的应用

本文通过聚乙烯吡咯烷酮（PVP）轻松地一锅溶剂热合成成功地合成了一种新型的BiOCl / TiO ₂分层复合材料。然后，通过场发射扫描电子显微镜（FESEM），透射电子显微镜（TEM），N ₂吸附/解吸，X射线功率衍射（XRD）分析，X射线光电子能谱（XPS）对制得的复合材料进行表征。），紫外可见漫反射光谱（DRS）和电化学阻抗光谱（EIS）。研究表明，这种新型复合材料对于形成BiOCl / TiO ₂表现出出众的可见光响应，增强的光活性和光稳定性。异质结。特别地，光催化剂的速率常数与锐钛矿型TiO ₂的摩尔比约30％以分解RhB，可达到约0.1510min ^-1，远优于市售的P25，制备的锐钛型TiO ₂纳米颗粒和单独的四方BiOCl。此外，超氧自由基（O ²⁻）和光生空穴（h ⁺）被证明是该光降解过程中的主要活性自由基。这项研究进一步表明，这种光催化剂的光活性增强应归因于BiOCl / TiO ₂异质结的成功形成和界面电荷的快速迁移。