Rationally designed Ta3N5/BiOCl S-scheme heterojunction with oxygen vacancies for elimination of tetracycline antibiotic and Cr(VI): Performance, toxicity evaluation and mechanism insight. (1st October 2022)

• Record Type: Journal Article
• Authors: Li, Shijie; Cai, Mingjie; Wang, Chunchun; Liu, Yanping; Li, Neng; Zhang, Peng; Li, Xin
• Is Part Of: Journal of materials science & technology. Volume 123(2022)
• Page Start: 177
• Page End: 190
• Publication Date: 2022-10-01
• Subjects: Ta3N5/BiOCl -- S-scheme heterojunction -- Oxygen vacancy -- Visible-light photocatalysis -- Antibiotic degradation -- Cr(VI) reduction; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2022.02.012
• Languages: English
• ISSNs: 1005-0302

Abstract

Highlights: 0D/3D Ta3 N5 /BiOCl S-scheme heterojunction with oxygen vacancies was constructed. Ta3 N5 /BiOCl exhibited excellent catalytic performance for removal of TC and Cr(VI). A plausible degradation pathway for TC was proposed and the toxicity assessment was performed. S-scheme heterojunction combined with OVs boosted charge separation, redox ability and ROS generation. Abstract: S-scheme heterojunction photocatalysts have been the "stars" in the field of photocatalysis. Herein, a novel S-scheme heterojunction of Ta3 N5 /BiOCl with oxygen vacancies (OVs) was fabricated via a facile method. The charge separation and transport mechanism of this Ta3 N5 /BiOCl S-scheme heterojunction was verified by the analyses of band energy structures, active species, photoelectric behaviors and DFT theoretical calculation. Compared with Ta3 N5 and BiOCl, the Ta3 N5 /BiOCl unveils substantially upgraded photocatalytic property under visible light, and the photocatalytic efficiency for removal of tetracycline (TC) and hexavalent chromium (Cr(VI)) reaches 89.6% and 91.6%, respectively. The substantial enhancement of the photocatalytic activity is attributed to the synergistic effect of the S-scheme hetero-structure and oxygen vacancies, which improves the visible-light absorption, while promoting the spatial separation of charge carriers with the optimum redox capacity, thereby boosting the production of active species for catalytic reactions. The TC degradation pathway is deduced and the toxicity evolution of TC is appraised using the QSAR method. In a nutshell, this work gives a deep understanding of the photocatalytic mechanism based on Ta3 N5 /BiOCl as well as presents a newfangled thought for developing highly efficient S-scheme heterojunction photocatalysts for water decontamination. Graphical abstract: A novel 0D/3D Ta3N5/BiOCl S-scheme heterojunction with oxygen vacancies has been fabricated and employed as a highly efficient and durable VLD photocatalyst for pharmaceutical antibiotic degradation and Cr(VI) reduction Image, graphical abstract