S‐g‐C₃N₄/N−TiO₂ @PTFE Membrane for Photocatalytic Degradation of Tetracycline

Abstract

Herein we synthesized S‐g‐C3N4 and N−TiO2 catalysts by hydrothermal and calcination technologies and SCN/NT@PTFE membrane by a vacuum filtration method. The morphology and composition of the synthesized materials were analyzed by different characterization methods (SEM/HRTEM/XRD/XPS/UV‐vis et.). The effects of different catalysts, pollutant concentrations, mass of catalyst and pH on the photo‐degradation of tetracycline were investigated. The degradation rate of tetracycline by SCN/NT‐2@PTFE membrane was as high as 99.9 % after 2 h of illumination. This was mainly because heterogeneous structure between S‐g‐C3N4 and N−TiO2 broadened the light absorption range and suppressed the carrier complex. Superoxide radicals (⋅O2−) were proved to play a dominant role in the degradation reaction. After 20 days of stirring in water, the photocatalytic performance of membrane decreased slightly, demonstrating its good stability. The study of SCN/NT‐2@PTFE membrane provides a new direction for the development of photocatalysis and membrane.

Advanced Stimuli-Responsive Structure Based on 4D Aerogel and Covalent Organic Frameworks Composite for Rapid Reduction in Tetracycline Pollution

“…Figure 5 a is the photocatalytic degradation kinetics curve of TC in 120 s. As expected, COF-1/BiPO 4 shows a faster degradation rate (0.391 min −1 ) than BiPO 4 (0.014 min −1 ) with the same conditions. As shown in Figure 5 b, the photocatalytic rate of COF-1/BiPO 4 is much faster than other previously reported photocatalysts, such as COF-TpTt composite (0.026 min −1 ), MOF-ZIF-8 composite (0.040 min −1 ), g-C 3 N 4 composites (0.070 min −1 and 0.028 min −1 ), and TiO 2 (0.038 min −1 ) [ 26 , 38 , 39 , 40 , 41 , 42 , 43 ]. From the foregoing, COF-1 is one of the main influences in improving the photocatalytic activity of COF-1/BiPO 4 .…”

Facile Synthesis to Porous TiO2 Nanostructures at Low Temperature for Efficient Visible-Light Degradation of Tetracycline

“…To further clarify the photodegradation pathway and mechanism of TC by TiO 2 , the degradation process of TC was predicted by the density functional theory (DFT) calculation. Based on density functional theory calculations, the Gaussian 16 program software and the Multiwfn program were used to perform abbreviated Fukui function calculations to reveal the reactivity between different atomic sites on the TC molecule and the dominant active oxide species in the TiO 2 system [ 27 , 69 , 70 ]. First, Gaussian was used to optimize the structure of TC molecules (as shown in Figure 11 a), and then the natural bond orbital (NBO) analysis was performed to calculate the single-point energy to obtain the NBO charge distribution of each atom of the optimized TC molecule under the disturbance of external electrons.…”

“…Finally, it generated P9 ( m / z = 60) and P10 ( m / z = 118) after decarboxylation. These intermediates will eventually be mineralized into small molecule harmless products such as CO 2 and H 2 O [ 27 , 43 , 62 ].…”

“…Further, the TC deluge contributes to the emergence of antibiotic-resistant bacteria and antibiotic-resistant genes [ 21 , 22 , 23 , 24 ]. At present, researchers have developed advanced oxidation, adsorption, microbial degradation and other technologies for the treatment of TC, among which photocatalytic oxidation is a typical advanced oxidation method [ 25 , 26 , 27 ]. In photocatalytic degradation, photocatalysts absorb solar energy to degrade antibiotics [ 28 , 29 ].…”