Abstract A Carbon quantum dots supported ZnO hollow Sphere (ZnO/C-dots) were synthesized through a solvothermal method using polyethylene glycol 400 (PEG 400) as a solvent. The phase and crystal structure of as-prepared ZnO/C-dots photocatalyst were characterized by powder X-ray diffraction (XRD). The surface morphology and size of the composite were analyzed using field emission scanning microscopy (FE-SEM). The optical properties of the as-prepared nanocomposites were examined using UV–visible (UV–Vis) spectrometer. The photocatalytic activity of pure ZnO and ZnO/C-dots nanocomposites were evaluated by the degradation of methylene blue (MB) under UV–Visible light irradiation. The ZnO/C-dots nanocomposites exhibited maximum photocatalytic MB dye degradation efficiency of 96% which is much higher that the pure ZnO (63%). The enhanced photocatalytic activity of ZnO/C-dots is due to the extended light absorption in the visible region and suppressed photoexcited electron-hole pair recombination rate. Moreover, the activity of photocatalyst after five cycles exhibits high stability, which is vital for the sustainable photocatalytic procedures. It is concluded that the prepared ZnO/C-dots composite have low cost, good stability and has a great potential application for Photocatalytic dye degradation.

中文翻译：

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用于染料降解应用的碳量子点负载氧化锌球基光催化剂

摘要 以聚乙二醇400（PEG 400）为溶剂，通过溶剂热法合成了碳量子点负载的ZnO空心球（ZnO/C-dots）。通过粉末 X 射线衍射 (XRD) 表征所制备的 ZnO/C 点光催化剂的相和晶体结构。使用场发射扫描显微镜（FE-SEM）分析复合材料的表面形态和尺寸。使用紫外-可见（UV-Vis）光谱仪检查所制备的纳米复合材料的光学性质。通过在紫外-可见光照射下降解亚甲蓝 (MB) 来评估纯 ZnO 和 ZnO/C 点纳米复合材料的光催化活性。ZnO/C-dots 纳米复合材料的最大光催化 MB 染料降解效率为 96%，远高于纯 ZnO（63%）。ZnO/C-dots 增强的光催化活性是由于在可见光区的光吸收扩展和抑制光激发电子-空穴对复合率。此外，五次循环后光催化剂的活性表现出高稳定性，这对于可持续的光催化过程至关重要。得出的结论是，所制备的ZnO/C-dots复合材料成本低、稳定性好，在光催化染料降解方面具有很大的应用潜力。