In this work, the carbon quantum dot (CQD)-decorated BiFeO3 nanoparticle photocatalysts were prepared by a hydrothermal method. The TEM observation and XPS characterization indicate that the CQDs are well anchored on the surface of BiFeO3 nanoparticles. Acid orange 7 (AO7) and hexavalent chromium (Cr(VI)) were chosen as the model pollutants to investigate the photocatalytic/photo-Fenton degradation and photocatalytic reduction performances of the as-prepared CQD/BiFeO3 composites under visible and near-infrared (NIR) light irradiation. Compared with bare BiFeO3 nanoparticles, the CQD/BiFeO3 composites exhibit significantly improved photocatalytic and photo-Fenton catalytic activities. Moreover, the composites possess good catalytic stability. The efficient photogenerated charges separation in the composites was demonstrated by the photocurrent response and electrochemical impedance spectroscopy (EIS) measurements. The main active species involved in the catalytic degradation reaction were clarified by radicals trapping and detection experiments. The underlying photocatalytic and photo-Fenton mechanisms are systematically investigated and discussed.

中文翻译：

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在可见光和近红外光照射下，CQD 修饰的 BiFeO3 纳米颗粒上 AO7 的光芬顿降解和 Cr(VI) 的光催化还原。

本工作采用水热法制备了碳量子点（CQD）修饰的BiFeO3纳米颗粒光催化剂。TEM 观察和 XPS 表征表明 CQD 很好地锚定在 BiFeO3 纳米粒子的表面。选择酸性橙 7 (AO7) 和六价铬 (Cr(VI)) 作为模型污染物，研究所制备的 CQD/BiFeO3 复合材料在可见光和近红外光下的光催化/光芬顿降解和光催化还原性能。 NIR）光照射。与裸露的BiFeO3纳米颗粒相比，CQD/BiFeO3复合材料表现出显着改善的光催化和光芬顿催化活性。此外，该复合材料具有良好的催化稳定性。光电流响应和电化学阻抗谱（EIS）测量证明了复合材料中有效的光生电荷分离。通过自由基捕获和检测实验阐明了参与催化降解反应的主要活性物种。系统地研究和讨论了潜在的光催化和光芬顿机制。