Porous g-C3N4 and α-FeOOH bridged by carbon dots as synergetic visible-light-driven photo-fenton catalysts for contaminated water remediation

Merging photocatalysis with Fenton-like reaction provides a promising synergetic advanced oxidation technology for water treatment, whereas the rational design of efficient cooperative photo-Fenton system still remains a great challenge. In this study, a ternary alpha-FeOOH/carbon dots/porous g-C3N4 (alpha-FeOOH/CDs/p-GCN) composite is developed as visible-light-driven heterogeneous photo-Fenton catalyst for contaminated water remediation. alpha-FeOOH nanorods are in-situ grown on porous g-C3N4 substrates, among which CDs are intercalated as high-speed electron transmission bridges, simultaneously preventing the photogenerated electron-hole recombination and accelerating the Fe3+/Fe2+ redox cycle. The distinctive heterostructure and synergetic catalytic effect endow alpha-FeOOH/CDs/p-GCN with superior efficiency, reusability, and universality for recalcitrant pollutant elimination, the reaction rate of which is nearly 13.6, 7.3, 3.4, 1.4, and 5.1 times higher than that of alpha-FeOOH, bulk g-C3N4 (b-GCN), p-GCN, alpha-FeOOH/p-GCN, and alpha-FeOOH/CDs/b-GCN, respectively. The FeOOH/CDs/p-GCN also demonstrates excellent tolerance to realistic environmental matrices including deionized water, sea water, river water, wastewater, and underground water. HO center dot and center dot O-2(-) radicals are proved to be the predominant contributors in the photo-Fenton system. This work provides an efficient synergetic visible-light-driven photo-Fenton catalyst possessing great potential for practical contaminated water remediation. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

A ternary composite has been developed as a visible-light-driven photo-Fenton catalyst, showing superior efficiency, reusability, and universality in contaminated water treatment.