PDINH bridged NH2-UiO-66(Zr) Z-scheme heterojunction for promoted photocatalytic Cr(VI) reduction and antibacterial activity

Z-scheme mechanism was a promising approach to considerably enhance photocatalytic activity. In this work, the PDINH/NH2-UiO-66(Zr) (PNU) heterojunctions were made using a facile ball-milling method. As expect, the optimum PNU-1 composite acted as highly active photocatalyst with 97% Cr(VI) to be reduced within 60 min of LED light illumination. Moreover, the antibacterial rate almost reached 100% for E. coli and S. aureus in 4 h, which was more conspicuous than the others. The wider light absorption range, promoted charge separation because of Z-scheme mechanism and efficient generation of reactive O-1(2), center dot O-2(-) , and center dot OH contributed greatly to the enhanced photocatalytic activity. Meanwhile, the superior stability and repeatability of the composites were also demonstrated by five cyclic experiments and related physicochemical characterizations. Therefore, this work provides a novel insight for designing high-efficiency Z-scheme heterostructures between MOFs and organic PDINH for wastewater remediation.

Automated summary

Z-scheme mechanism was used to enhance the photocatalytic activity. PDINH/NH2-UiO-66(Zr) (PNU) heterojunctions were prepared using a ball-milling method. The PNU-1 composite showed excellent photocatalytic activity, reducing 97% of Cr(VI) within 60 minutes of LED light illumination. The composite also exhibited high antibacterial efficiency against E. coli and S. aureus. The enhanced photocatalytic activity was attributed to the wider light absorption range, efficient charge separation, and generation of reactive species. The stability and repeatability of the composites were also demonstrated. This work provides new insights for designing efficient Z-scheme heterostructures for wastewater remediation.