Utilizing photocatalysis to remove antibiotics from aqueous solution is a promising technology for environmental remediation. In this work, we successfully fabricated a visible-light-responsive and magnetically recycled carbon dot (CD)/NiCo₂O₄ composite photocatalyst through a one-step simple calcination method for the first time. Compared with pristine NiCo₂O₄, CDs/NiCo₂O₄ composites exhibit significantly enhanced photocatalytic activity for the degradation of tetracycline (TC) (100 mL, 10 mg L⁻¹) under visible-light irradiation. The photodegradation rate constant data reveal that CDs/NiCo₂O₄ with 3 wt% CD loading content (CDs/NiCO-3) exhibited the highest photocatalytic activity (0.02134 min⁻¹), which is about 6-fold in comparison with pristine NiCo₂O₄ (0.0036 min⁻¹). The enhanced photocatalytic activity of the CDs/NiCo₂O₄ composite corresponds to the synergetic effect of CDs and NiCo₂O₄ that improves not only the light absorption capacity but also the separation efficiency of photo-induced charge carriers. Additionally, the CDs/NiCo₂O₄ composites showed good recyclability without loss of apparent photocatalytic activity after five successive cycles, and more importantly, CDs/NiCo₂O₄ could be recovered magnetically.

中文翻译：

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制备具有光催化活性的可磁分离和可回收的碳点/ NiCo ₂ O ₄复合材料，用于在可见光下降解四环素†

利用光催化从水溶液中去除抗生素是一种有前途的环境修复技术。在这项工作中，我们首次通过一步简单的煅烧方法成功制备了可见光响应和磁循环的碳点（CD）/ NiCo ₂ O ₄复合光催化剂。与原始NiCo ₂ O ₄相比，CDs / NiCo ₂ O ₄复合材料在可见光照射下对四环素（TC）（100 mL，10 mg L ^-1）的降解表现出显着增强的光催化活性。光降解速率常数数据表明，CDs / NiCo ₂ O ₄具有3 wt％CD负载含量（CDs / NiCO-3）的CD / NiCO-3表现出最高的光催化活性（0.02134 min ^-1），是原始NiCo ₂ O ₄（0.0036 min ^-1）的约6倍。CDs / NiCo ₂ O ₄复合材料增强的光催化活性对应于CDs和NiCo ₂ O ₄的协同作用，不仅提高了光吸收能力，而且提高了光诱导电荷载流子的分离效率。另外，CD / NiCo ₂ O ₄连续五个循环后，复合材料显示出良好的可回收性，并且没有损失任何明显的光催化活性，更重要的是，CDs / NiCo ₂ O ₄可以通过磁性回收。