Construction of heteropolyacid-anchored magnetic g-C3N4/Fe3O4@polyindole hybrids for efficient photocatalytic destruction of methyl orange and bacteria

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Chemistry., 2023-10, Vol.444, p.114923, Article 114923
• Main Authors: Ibrahim Elaibi, Alaa, Ammar, Saad H., Sh. Mohammed, Israa, Jabbar, Zaid H.
• Format: Article
• Language: English
• Subjects: Heteropolyacids; Magnetic g-C3N4; Methyl orange; P. aeruginosa; Photocatalytic degradation; Polyindole
• ISSN: 1010-6030
• DOI: 10.1016/j.jphotochem.2023.114923

[Display omitted] •g-C3N4/Fe3O4@PID-TPA hydride photocatalyst has been synthesized.•The g-C3N4/Fe3O4@PID-TPA exhibited high degradation performance against MO dye and P. aeruginosa bacteria.•The cytotoxic effect of g-C3N4/Fe3O4@PID-TPA was assessed, reaching 29% reduction in the HCT116 cell viability.•A strong synergetic impact of TPA and PID with magnetic g-C3N4.•g-C3N4/Fe3O4@PID-TPA photocatalyst recycled five times without losing its performance. Given the treatment of wastewater contaminated with organic dyes and bacteria, it is essential to fabricate high-performance, eco-friendly, and cost-effective photocatalytic materials. Herein, a new separatable and efficient organic–inorganic hybrid composite of tungstophosphoric acid(TPA) anchored by conducting polyindole (PID) onto magnetic graphitic carbon nitride (g-C3N4) was synthesized and used for photocatalytic degradation of methyl orange (MO) and gram-negative bacteria (P. aeruginosa) in the presence of visible LED illumination. The obtained g-C3N4/Fe3O4@PID-TPA photocatalyst was characterized by XRD, VSM, FESEM, EDX, TEM, BET surface area, DRS, PL, and FTIR methods. The g-C3N4/Fe3O4@PID-TPA catalyst (0.1 g/l catalyst dose) revealed high destruction activity (97.5%) for MO within 70 min. Due to the presence of controllable electronic structured g-C3N4, conductive PID polymer, and highly redox property of TPA heteropolyacid, boosted degradation activity was achieved by the g-C3N4/Fe3O4@PID-TPA heterostructure. Besides, the magnetic g-C3N4/Fe3O4@PID-TPA catalysts could be recycled five times without reduction in their photocatalytic performances. The g-C3N4/Fe3O4@PID-TPA catalyst demonstrates extraordinary antibacterial activity against P. aeruginosa (94.49%) at low g-C3N4/Fe3O4@PID-TPA dose. Besides, the antibacterial mechanism showed that the synergistic performance between g-C3N4/Fe3O4@PID and TPA harms the cell membranes, improves the levels of oxidative stress, and ultimately kills of P. aeruginosa. Also, the cytotoxic effect of g-C3N4/Fe3O4@PID-TPA catalyst was assessed in vitro by a MTT assay (achieving 25% to 29 % reduction in the colorectal carcinoma HCT116 cell viability). This work introduces a new outlook on developing organic–inorganic composite as photocatalysts based on heteropolyacids that serve multiple functions, particularly for environmental applications.