Boosted Photocatalytic Degradation of Atrazine Using Oxygen-Modified g-C3N4: Investigation of the Reactive Oxygen Species Interconversion

Qintian Peng; Liqun Ye; Li Wang; Xin Ying Kong; Hailin Tian; Yingping Huang; Yiqun Tian; Xiang Liu; Honglin Liu

doi:10.1021/acs.langmuir.3c03183

Boosted Photocatalytic Degradation of Atrazine Using Oxygen-Modified g-C₃N₄: Investigation of the Reactive Oxygen Species Interconversion

Langmuir. 2024 Jan 23;40(3):1848-1857. doi: 10.1021/acs.langmuir.3c03183. Epub 2024 Jan 6.

Authors

Qintian Peng^{1

2}, Liqun Ye^{2

3}, Li Wang^{1

2}, Xin Ying Kong⁴, Hailin Tian^{2

3}, Yingping Huang^{1

2}, Yiqun Tian⁵, Xiang Liu^{2

3}, Honglin Liu^{1

2}

Affiliations

¹ College of Hydraulic & Environmental Engineering, China Three Gorges University, Yichang 443002, China.
² Engineering Research Center of Eco-environment in Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Yichang 443002, China.
³ College of Materials and Chemical Engineering, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, China Three Gorges University, Yichang 443002, China.
⁴ School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371 , Singapore.
⁵ Hubei Xingfa Chemicals Group Co., Ltd., Yichang 443002, China.

PMID: 38183664
DOI: 10.1021/acs.langmuir.3c03183

Abstract

Elaborating the specific reactive oxygen species (ROS) involved in the photocatalytic degradation of atrazine (ATZ) is of great significance for elucidating the underlying mechanism. This study provided conclusive evidence that hydroxyl radicals (·OH) were the primary ROS responsible for the efficient photocatalytic degradation of ATZ, thereby questioning the reliability of widely adopted radical quenching techniques in discerning authentic ROS species. As an illustration, oxygen-modified g-C₃N₄ (OCN) was prepared to counteract the limitations of pristine g-C₃N₄ (CN). Comparative assessments between CN and OCN revealed a remarkable 10.44-fold improvement in the photocatalytic degradation of ATZ by OCN. This enhancement was ascribed to the increased content of C-O functional groups on the surface of the OCN, which facilitated the conversion of superoxide radicals (·O₂^-) into hydrogen peroxide (H₂O₂), subsequently leading to the generation of ·OH. The increased production of ·OH contributed to the efficient dealkylation, dechlorination, and hydroxylation of ATZ. Furthermore, toxicity assessments revealed a significant reduction in ATZ toxicity following its photocatalytic degradation by OCN. This study sheds light on the intricate interconversion of ROS and offers valuable mechanistic insights into the photocatalytic degradation of ATZ.