In this study, novel carbon dots/BiPO₄ (CDBP) photocatalytic complexes were successfully synthesized via a facile hydrothermal-calcination synthesis strategy. The physicochemical properties of the synthesized samples were studied by X-ray diffraction (XRD), UV–vis diffuse reflectance spectra (DRS), Fourier infrared spectrometer (FT-IR), Raman spectrometer, scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), photoluminescence26spectra (PL), electrochemical workstation, etc. The activities of the CDBP were evaluated through the photocatalytic degradation of Indometacin(IDM) in an aqueous solution under simulated sunlight irradiation. With increasing concentrations of carbon dots (CDs), the photocatalytic activity of the CDBP initially increased, and then decreased. A CDs content of 3.0 wt% shows 12 times higher photocatalytic activity than that of pristine BiPO₄. Reactive oxidative species, particularly O₂⁻ and h⁺, were the two critical reactive oxidative species to mediator immediate the photocatalytic degradation of IDM. A notable sign of 5, 5-dimethyl-1-pyrrolidone-N-oxyl(DMPOX) was observed through electron spin resonance spectroscopy(EPR) with CDBP as the photocatalyst, which indicated higher oxidability than pristine BiPO₄ under simulated sunlight irradiation. This enhanced photocatalytic activity might due to high-efficiency charge separation, unique up-converted PL properties, as well as the bandgap narrowing of the CDs. Moreover, the byproducts of IDM were detected by HPLC-MS/MS and GC-MS, and the probable pathways were deduced. The acute toxicity at three trophic levels initially increased slowly and then decreased rapidly as the IDM dechlorination and total organic carbon(TOC) decreased during photocatalytic degradation.

中文翻译：

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模拟的阳光活化CD加载的BiPO ₄光催化剂降解吲哚美辛的作用：氧化物种的作用。

在这项研究中，新型碳点/ BiPO ₄（CDBP）光催化配合物已成功地通过简便的水热煅烧合成策略合成。通过X射线衍射（XRD），紫外可见漫反射光谱（DRS），傅立叶红外光谱仪（FT-IR），拉曼光谱仪，扫描电子显微镜（SEM），高分辨率透射率研究了合成样品的理化性质。电子显微镜（HRTEM），光致发光26光谱（PL），电化学工作站等。CDBP的活性通过在模拟阳光照射下水溶液中吲哚美辛（IDM）的光催化降解来评估。随着碳点（CDs）浓度的增加，CDBP的光催化活性开始增加，然后下降。CD的内容为3。₄。反应性氧化物质，特别是O ₂^-和h ⁺是介导IDM光催化降解的两个关键反应性氧化物质。通过电子自旋共振光谱（EPR），以CDBP为光催化剂，观察到5，5-二甲基-1-吡咯烷酮-N-氧基（DMPOX）的显着信号，表明其氧化能力高于原始BiPO ₄在模拟的阳光照射下。这种增强的光催化活性可能归因于高效电荷分离，独特的上转换PL特性以及CD的带隙变窄。此外，通过HPLC-MS / MS和GC-MS检测IDM的副产物，并推论出可能的途径。随着光催化降解过程中IDM脱氯和总有机碳（TOC）的降低，三个营养级的急性毒性开始缓慢上升，然后迅速下降。