Effective mineralization and detoxification of tetracycline hydrochloride enabled by oxygen vacancies in g-C3N4/ LDH composites

• Published in: Separation and purification technology 2023-01, Vol.305, p.122554, Article 122554
• Main Authors: Zheng, Jiangfu, Fan, Changzheng, Li, Xiaoming, Yang, Qi, Wang, Dongbo, Duan, Abing, Pan, Shuaijun, Zhang, Baowei, Ding, Jinglin, Rong, Shengxiang, Yin, Haoyu
• Format: Article
• Language: English
• Subjects: Detoxification; g-C3N4; Oxygen vacancy; Visible-light photocatalysis; ZnAl-LDH
• ISSN: 1383-5866; 1873-3794
• DOI: 10.1016/j.seppur.2022.122554

[Display omitted] •An oxygen vacancy-rich g-C3N4/LDH S-scheme heterojunction system was constructed.•Oxygen vacancies can facilitate light absorption promote the generation of radicals.•There is a synergistic effect between S-scheme heterojunctions and oxygen vacancies.•Oxygen-rich vacancy of g-C3N4/LDH0.3 S-scheme heterojunction with better mineralization and detoxification. Development of efficient nanomaterials for photocatalytic degradation is very important in the removal of organic pollutants from water. The oxygen vacancy-rich g-C3N4/ LDH composites (g-C3N4/LDH-OVs) with a layered structure was prepared for the efficient photocatalysis degradation and mineralization of tetracycline hydrochloride (TC) under visible light irradiation. Oxygen vacancies in the composites achieved through structural induction strategy not only provide abundant active sites but also improve the separation efficiency of the photo-generated carriers, thereby enhancing the degradation and mineralization of TC, as revealed both by theories and experiments. The optimized g-C3N4/LDH-OVs have achieved excellent photocatalytic activity (i.e., 95 % degradation and 28 % mineralization of TC after 60 min of visible light irradiation), which was 2.3 and 3.5 times higher than that of the pristine g-C3N4 and LDH-OVs, respectively. Furthermore, experimental results based on bio-acute toxicity show that the g-C3N4/LDH-OVs/Vis system can effectively detoxify the transformation products. This study provides an insight into the development of LDH-based photocatalysts, so as to realize photocatalytic mineralization and simultaneous detoxification through the new strategy of oxygen vacancy defect engineering.