A type II heterojunction α-Fe2O3/g-C3N4 for the heterogeneous photo-Fenton degradation of phenol

The heterogeneous photo-Fenton reaction is an effective method of chemical oxidation to remove phenol in wastewater with environmental friendliness and sustainability. Herein, the composite alpha-Fe2O3/g-C3N4, as a catalyst of the heterogeneous photo-Fenton reaction, has been synthesized by hydrothermal-calcination method using the abundant and low-cost FeCl3 center dot 6H(2)O and g-C3N4 as raw materials. The influence of the annealing temperature during calcination was also investigated. The UV-Vis diffuse reflectance spectra of samples show that the composite alpha-Fe2O3/g-C3N4 possesses the widest light response range. Furthermore, the transient photocurrent response curves demonstrated the strongest intensity of alpha-Fe2O3/g-C3N4. The annealed alpha-Fe2O3/g-C3N4 is indicative of the highest degradation efficiency in all samples due to the improvement of the charge transfer ability caused by the tight heterojunction structure. The results of the scavenger trapping experiments show that the hydroxyl radical was the main active species in degradation. Based on experimental results, a type II heterojunction should be built in the composite alpha-Fe2O3/g-C3N4, driving the photoelectrons transfer and migration by internal electronic field. This work provides a facile and new method to synthesize alpha-Fe2O3/g-C3N4 as an effective heterogeneous photo-Fenton catalyst for environmental remediation.

Automated summary

This study synthesized α-Fe2O3/g-C3N4 composite as a heterogeneous photo-Fenton catalyst using a hydrothermal-calcination method and investigated the influence of annealing temperature. The results showed that the annealed α-Fe2O3/g-C3N4 sample exhibited the highest degradation efficiency due to the improved charge transfer ability caused by the tight heterojunction structure.