Preparation Of Magnetically Separable ZnFe₂O₄ Photocatalyst And Its Photocatalytic Performance Toward Antibiotics

A highly efficient and easily recoverable catalyst is always desirable for practical photocatalytic applications.In this study,a magnetically separable ZnFe₂O₄/NCDs/Ag₂CO₃ Z-scheme heterojunction photocatalyst using nitrogen doped carbon quantum dots（NCDs）as solid-state electron mediators was fabricated by an easy-operated deposition-precipitation method.The prepared ZnFe₂O₄/NCDs/Ag₂CO₃ photocatalyst exhibits a promoted photocatalytic activity for Levofloxacin（LVFX）removal compared to single ZnFe₂O₄ and Ag₂CO₃,achieving 88.75%and 22.53%degradation efficiency under visible and near-infrared（NIR）light irradiation,respectively.Characterization results show that the synergistic effect of remarkable charge carrier separation efficiency and broadened solar light absorption is responsible for the enhanced photocatalytic performance.The well-matched band structures of the two semiconductors facilitate the charge transfer in Z-scheme transfer model,resulting in high charge separation rate.Simultaneously,due to the superb electron transfer character of NCDs,the introduction of NCDs can further accelerate the transfer of the photogenerated charges as solid-state electron mediators between ZnFe₂O₄ and Ag₂CO₃.Furthermore,the unique up-converted photoluminescence properties of NCDs can broaden the optical absorption of the prepared ZnFe₂O₄/NCDs/Ag₂CO₃ to NIR region,thus leading to an enhanced utilization of solar energy.This work provides a novel insight into the fabrication of novel all-solid-state Z-scheme photocatalyst based on nitrogen doped carbon quantum dots and opens new vista for the design of magnetically separable and highly efficient photocatalysts for environmental remediation.