N-Doped carbon dots decorated ceria hollow spheres for enhanced activity of RhB degradation by visible light

The fabrication of low-cost and environmentally friendly photocatalysts with superior photodegradation efficiency remains one of the most pressing challenges in present research. Herein, we elaborately designed and synthesized a promising N-doped carbon quantum dots/CeO 2 hollow microsphere (NCQDs/h-CeO 2 ) photocatalyst with superior photoresponse property and photoactivity in visible light. The removal efficiencies of rhodamine B (RhB) under visible light illumination for NCQDs/h-CeO 2 exhibits a 30.3% enhancement compared with pure h-CeO 2 . The results of EIS and PL imply that the excellent performance may be attributed to the strong synergistic effect between NCQDs and h-CeO 2, thus effectively promoting charge transfer and restraining the recombination of photogenerated holes and electrons. Accordingly, a synergistic photocatalysis mechanism was proposed to explain the photocatalytic reaction process. Besides, the NCQDs/h-CeO 2 exhibits better cycle stability than common CQDs/h-CeO 2 after a four-cycle photocatalytic test. Therefore, the NCQDs/h-CeO 2 may represent a promising strategy for the current water pollution issues.