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The immobilization of catalysts hinders the application of nanosized photocatalysts in wastewater treatment. In this study, a simple method for the preparation of flexible composite non-woven catalysts with a good spectral response is presented. Firstly, the porous g-C3N4 nanosheets containing nitrogen defects (DCN) and sodium alginate (SA) were blended to prepare the casting solution and then coated on the surface of polyester and viscose blend non-woven fabric (NW). Finally, the robust three-dimensional composite non-woven catalyst (DCN@SA/NW) was constructed by cross-linking with CaCl2. The as-prepared samples were characterized by different physicochemical techniques including SEM, EDS, FTIR, Raman, XRD, XPS, and TGA. The photocatalytic degradation of dyes and antibiotics and self-cleaning and antibacterial properties of the catalyst were investigated. The optimal DCN@SA/NW formulation was 2.0 wt.% DCN and 2.0 wt.% SA. The DCN@SA/NW composite efficiently degraded rhodamine (RhB) and tetracycline hydrochloride (TC). Moreover, the synthesized non-woven composite catalyst was easily recycled and remained stable, indicating its promising potential in wastewater treatment. The DCN@SA/NW also exhibited outstanding self-cleaning and antibacterial performance. This study provides an interesting idea for the research and development of immobilized photocatalysts and has great potential in future practical photocatalytic applications. [ABSTRACT FROM AUTHOR]

In present study, an efficient ternary Ag/TiO2/mesoporous g-C3N4 (M-g-C3N4) photocatalyst was successfully synthesized through depositing Ag nanoparticles (NPs) on the surface of TiO2/M-g-C3N4 heterojunction. Ag/TiO2/M-g-C3N4 nanocomposite displayed the highest degradation efficiency for amoxicillin (AMX) compared to TiO2/M-g-C3N4 heterojunction, M-g-C3N4, and bulk-g-C3N4 (B-g-C3N4). The removal efficiency of AMX in real situation, surface water (SW), hospital wastewater (HW), and waste water treatment plant (WWTP) also were studied to illustrate the effectiveness of Ag/TiO2/M-g-C3N4 photocatalysts. The vulnerable atoms in AMX structure were revealed through DFT calculation. Additionally, the dominating active groups produced in time of the photocatalytic procedure were determined on account of free radical trapping experiments and ESR spectra. The mechanism of photocatalytic degradation was proposed and verified. The transfer of the electrons and the inhibition of the recombination of photogenerated electron-holes were enhanced effectively under the synergistic effect of the Ag NPs and TiO2. As a consequence, the catalytic activity of the composite was improved under visible light. [ABSTRACT FROM AUTHOR]

In this work, a series of mesoporous graphitic carbon nitride (MCN) nanometer materials, loaded onto the reduced graphene oxide aerogel (rGOA) with macroscopic three-dimensional (3D) porous structure, were prepared using reduction self-assembly method. The composite aerogel of MCN/rGOA hybrid (MCN/GO mass ratio of 3:9) showed the highest adsorption rate of 73.7% for removing rhodamine b (RhB) solution of 20 mg L−1, whereas the total effect of adsorption and visible-light catalysis reached 95.2% within 80 min. Meanwhile, the material also showed good stability, and the removal rate was still about 89% after repeating the experiments for five times. The material characterization was carried out using various techniques, which indicated that hybrid aerogels were successfully combined. The specific surface increases from 18 m2/g of MCN to 149 m2/g for MCN/rGOA hybrid. The hybrid aerogel not only has good adsorption effect, but also exhibits adequate photocatalysis. The composite firstly interacts with the RhB through π–π adsorption, and then, the photocatalysis is improved by increasing the electron transfer efficiency and inhibiting the electron–hole recombination for good conductivity. Through scavenger experiments, it is shown that h+ free radicals are the dominant oxidizer during photocatalytic degradation. [ABSTRACT FROM AUTHOR]