α-Fe2O3/Cu2O(SO4) composite as a novel and efficient heterogeneous catalyst for photo-Fenton removal of Orange II

Hematite (α-Fe 2 O 3 ), as one of Fenton reagents, is widely investigated for the treatment of wastewater in the field of advanced oxidation processes (AOPs). Considering the fast charge carrier recombination of hematite (α-Fe 2 O 3 ), we have successfully synthesized a novel and high active heterogeneous Fenton catalyst α-Fe 2 O 3 /Cu 2 O(SO 4 ) for the degradation of organic pollutants. The results show that the as-obtained Cu 2 O(SO 4 )-Fe9 composite exhibits excellent degradation properties of Orange II. 98.9% degradation rate was achieved for 100 mL of 50 mg/L Orange II solution in the condition of 0.3 g/L Cu 2 O(SO 4 )-Fe9 catalyst, 3 mM H 2 O 2 and pH = 3.5. The degradation rate constants of Cu 2 O(SO 4 )-Fe9 in the photo-Fenton-like system are 9.33 and 4.07 times of Cu 2 O(SO 4 ) and α-Fe 2 O 3 , respectively. In addition, the mechanism and pathway for the degradation of Orange II were proposed. The scheme of combining copper-based oxysulfate Cu 2 O(SO 4 ) with hematite (α-Fe 2 O 3 ) could improve the efficiency of charge carrier separation, which will further enhance the catalytic activity and expand its application in water purification.