A type II heterojunction α-Fe(2)O(3)/g-C(3)N(4) 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 α-Fe(2)O(3)/g-C(3)N(4), as a catalyst of the heterogeneous photo-Fenton reaction, has been synthesized by hydrothermal-calcination method using the abundant and low-cost FeCl(3)·6H(2)O and g-C(3)N(4) 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 α-Fe(2)O(3)/g-C(3)N(4) possesses the widest light response range. Furthermore, the transient photocurrent response curves demonstrated the strongest intensity of α-Fe(2)O(3)/g-C(3)N(4). The annealed α-Fe(2)O(3)/g-C(3)N(4) 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 α-Fe(2)O(3)/g-C(3)N(4), driving the photoelectrons transfer and migration by internal electronic field. This work provides a facile and new method to synthesize α-Fe(2)O(3)/g-C(3)N(4) as an effective heterogeneous photo-Fenton catalyst for environmental remediation.