Chun-Yang Li,Lu Yang,Yingshuang Lu,Man-Man Wang,Jing-Min Liu,Shuo Wang
Photocatalysis-based advanced oxidation technologies have been developed as an attractive strategy for degrading pollutants. However, the question of how to increase removal specificity without sacrificing the degradation effect remains a difficult one. In this work, a photocatalytic system for the simultaneous targeted elimination of nine heterocyclic amines (HCAs) is established using a green-prepared photocatalyst (CN@Mn–FeOOH@MIP) that activates sodium persulfate (PS) under visible light. Mn–FeOOH clusters are in situ covered on laminar g-C 3 N 4 (CN) carrier to form a heterojunction, along with a molecularly imprinted layer self-polymerized from dopamine, which is grown on the outer layer, resulting in both the desired photochemical activity and specific sites for recognition. The conditions of composite and photocatalysis are explored and optimized for efficient and selective degradation. Notably, CN@Mn–FeOOH@MIP is synthesized free of any organic reagents, and the biosafety is confirmed by cellular and in vivo toxicity evaluation. The developed CN@Mn–FeOOH@MIP/PS system with visible-light-driven is applied to the removal of HCAs in coffee samples with the recoveries over 70% and the reuse rates greater than 85%. It coupled the advantages of specific enrichment and rapid degradation, which furnishes a novel approach for the control of trace thermal processing pollutants.
Yao Deng,Yanmei Li,Jing Wang,Huidi Zhang,Lin Wang,Qiong Wang,Tao Xu,Wenlei Wang
Nitrogen deficient porous nanosheets(NDCN) are a promising nano template that can combine defect engineering with Mn-FeOOH to suppress photo generated carrier complexation and optimize electron distribution . In this study, a unique structure with N/O double vacancies in Mn-FeOOH@NDCN was prepared using a magnesium thermal denitrification co-precipitation method. Furthermore, a series of Mn-FeOOH/NDCN/PMS reaction systems were constructed by adjusting the dosage of peroxymonosulfate(PMS). The experimental results indicate that the synergistic activation of N/O double vacancies on PMS enables the Mn-FeOOH/NDCN/PMS system to oxidize almost 10 mg/L of As(III) within 90 min. At the same time, the oxidized As(V) was completely adsorbed, thereby completely removing the total arsenic in the water. The reasonable construction of carbon networks is a prerequisite for the stability of Mn-FeOOH/NDCN composite catalysts, enabling them to have good cyclic stability. The experimental results confirm that oxygen vacancies directly participate in the activation of PMS, while nitrogen vacancies effectively adsorb As(III), thereby promoting the contact between As(III) and PMS, improving the mass transfer rate, and accelerating the catalytic degradation process. This study will provide a new way to completely remove arsenic pollution from water bodies.