Ternary hybrid Ag/SnO2-X/Bi4O5I2 photocatalysts: Impressive efficiency for photocatalytic degradation of antibiotics and inactivation of bacteria

• Published in: Applied surface science 2022-12, Vol.606, p.154610, Article 154610
• Main Authors: Liu, Juan, Shu, Shuangxiu, Li, Yeping, Liu, Jiawei, Yao, Jiao, Liu, Shuai, Zhu, Menghao, Huang, Liying, Huang, Lijing
• Format: Article
• Language: English
• Subjects: Ag/SnO2-x/Bi4O5I2; Antibacterial; Degradation; LED light; Photocatalyst
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2022.154610

Novel Ag/SnO2-x/Bi4O5I2 ternary composites were prepared by introducing Ag nanoparticles in SnO2-x/Bi4O5I2 binary composites. Ag nanoparticles as an electron transport bridge is beneficial to the separation of photocarriers. The noble metal surface plasmon resonance (SPR) effect of Ag nanoparticles can also enhance the visible light absorption performance of the composites. 3% Ag/SnO2-x/Bi4O5I2 can degrade 80% TC in 120 min, inactivate E. coil in 15 min and S. aureus in 20 min. [Display omitted] •A novel Z-scheme Ag/SnO2-x/Bi4O5I2 ternary composite was prepared.•Ag/SnO2-x/Bi4O5I2 can effectively remove E. coli, S. aureus and TC under LED light.•h+, e- and •OH are main active species.•Ag nanoparticles are in favor of the separation of carriers and light absorption.•Z-scheme in the composite promoted the separation of charges and its redox ability. Ag/SnO2-x/Bi4O5I2 ternary composites were prepared to further improve the photocatalytic properties by introducing Ag nanoparticles into SnO2-x/Bi4O5I2 binary composites. X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) proved that the ternary composites were successfully synthesized. Photocurrent and electrochemical impedance tests (EIS) confirmed that the photogenerated carrier separation efficiency of Ag/SnO2-x/Bi4O5I2 was much higher than SnO2-x and Bi4O5I2. Ag/SnO2-x/Bi4O5I2 showed high efficiency in degradation and antibacterial. The optimum sample of 3% Ag/SnO2-x/Bi4O5I2 can degrade 80 % tetracycline (TC) in 120 min, inactivate Escherichia coli (E. coil) in 15 min and Staphylococcus aureus (S. aureus) in 20 min under the LED light. The intermediates of the degradation of TC were identified by mass spectrometry (MS). Scanning electron microscopy (SEM) and confocal laser scanning microscope (CLSM) images intuitively showed the death process of E. coil caused by the photocatalytic reaction. The results of the capture experiment identified the active substance, and the possible photocatalytic degradation pathway was proposed. Ag/SnO2-x/Bi4O5I2 followed the Z-scheme charge transfer mechanism.