Accelerated Fenton degradation of azo dye wastewater via a novel Z-scheme CoFeN-g-C3N4 heterojunction photocatalyst with excellent charge transfer under visible light irradiation

Shihao Miao; Hongcheng Gao; Hongyu Xia; Xiaoxia Mao; Lijuan Zhang; Mengqin Shi; Yuanguang Zhang

doi:10.1039/d2dt02790a

Accelerated Fenton degradation of azo dye wastewater via a novel Z-scheme CoFeN-g-C₃N₄ heterojunction photocatalyst with excellent charge transfer under visible light irradiation

Dalton Trans. 2022 Nov 21;51(45):17192-17202. doi: 10.1039/d2dt02790a.

Authors

Shihao Miao¹, Hongcheng Gao¹, Hongyu Xia¹, Xiaoxia Mao¹, Lijuan Zhang¹, Mengqin Shi¹, Yuanguang Zhang^{1

2}

Affiliations

¹ Key Laboratory of Aqueous Environment Protection and Pollution Control of Yangtze River in Anhui of Anhui, Provincial Education Department, College of Resources and Environment, Anqing Normal University, Anqing 246011, China. hongchenggao@aqnu.edu.cn.
² College of Chemistry and Chemical Engineering, Anqing Normal University, Anqing 246011, China.

PMID: 36314543
DOI: 10.1039/d2dt02790a

Abstract

A novel Z-scheme heterostructure photocatalyst, CoFeN-g-C₃N₄ (CFN-CN), was prepared by a simple strategy, and its heterostructure and a photo-Fenton system were used to synergistically catalyze the degradation of azo dyes. The experimental results showed that the CFN-CN1 heterojunction exhibited superior photocatalytic degradation performance, and the degradation rate of Methyl Orange (MO) reached 96.8% in 40 min. The degradation rate constants were 11.8 and 2.81 times those of CN and CFN, respectively. CFN-CN1 also shows excellent catalytic degradation performance for other azo dyes (Congo Red (CR), Acid Orange 7 (AO7), Mordant Black 17 (MB17) and Acid Red B (ARB)), and the degradation efficiencies all exceeded 90%. Furthermore, the addition of inorganic anions (Cl^-, HCO₃^- and SO₄^2-) affects the degradation of azo dyes, especially HCO₃^- which significantly promotes the degradation of MO. The radical trapping experiments and EPR results indicated that superoxide radicals (˙O₂^-) and hydroxyl radicals (˙OH) were the main active species. The above research reveals that the CFN-CN heterojunction synergistic photo-Fenton system may provide new hints for the degradation and removal of azo dyes from wastewater.