Comparison of photocatalytic and antibacterial activities of allotropes of graphene doped Sm₂O₃ nanocomposites: Optical, thermal, and structural studies

Abstract

This study mainly focuses on the synthesis of two allotropes of graphene, graphene oxide (GO) and reduced graphene oxide (rGO), by the modified Hummers' method and chemical reduction method, respectively. Sm 2 O 3 /GO and Sm 2 O 3 /rGO nanocomposites were further synthesized in the presence of the cationic surfactant CTAB via the sol-gel method followed by the reflux method. Synthesized nanocomposites were subjected to characterization by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and UV-Visible spectroscopy to explore structural, thermal, optical, and photocatalytic properties. Characteristic FTIR peaks were observed in nanocomposites, and the bond length of the Sm-O bond was calculated. The Coats-Redfern method was employed to calculate the kinetics and thermodynamic parameters. Hexagonal crystallite shapes of Sm 2 O 3 /GO and Sm 2 O 3 /rGO nanocomposites with 11.8 and 13.13 nm crystallite sizes and 3.9 and 2.5 eV optical band gaps were observed. The photocatalytic efficiency of Sm 2 O 3 /GO and Sm 2 O 3 /rGO nanocomposites was assessed against the degradation of methylene blue in the presence of sunlight, and its degradation was confirmed through FTIR. The antimicrobial activities were also performed against the bacterial strains Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus.

The Impact of Different Green Synthetic Routes on the Photocatalytic Potential of FeSnO2 for the Removal of Methylene Blue and Crystal Violet Dyes under Natural Sunlight Exposure

“…Moreover, the FT-IR spectra of dyes after 60 and 120 min of sunlight exposure in the presence of the FeSnO 2 nanocomposite synthesized from Lawsonia inermis leaf extract during the degradation process were recorded to establish the existence of new functional groups which further justify the degradation process. Figure 13a shows a band in the region of 1500-1700 cm −1 depicting the aromatic ring structure and showing C=C stretching diminishing gradually until 2 h. It is evident from Figure 13a that in the case of degraded MB, the above-mentioned peaks are absent, while the appearance of a small peak in the region of 1000-1100 cm −1 shows the formation of a new fragment [46]. The peak at 3400-3500 cm −1 in the CV FTIR spectrum (Figure 13b) is ascribed to the stretching vibration of the hydroxyl group.…”

Elucidating the structural, catalytic, and antibacterial traits of Ficus carica and Azadirachta indica leaf extract‐mediated synthesis of the Ag/CuO/rGO nanocomposite

“…Suspension of 1 g of GO was prepared in 10 mL distilled water and it was kept on hot plate under magnetic stirring at 60°C temperature for 1 h. The above prepared plant extract was added to the reaction mixture under stirring with a feed rate of 4 mL/7 min for 1 h. The obtained solution was dark black and this was centrifuged at 8000 rpm for 5 min then product was washed with distilled water and ethanol to get rid of all impurities. The product was dried in an oven at 60°C followed by grinding to get a fine powder of rGO (Javaid & Farrukh, 2023).…”

Nitazoxanide and azithromycin for the early treatment of COVID‐19: A multi‐spectroscopic, biochemical and computational drug–drug interaction study

“…Bacterial inoculum (1 Â 10 5 cells) was added to each well of the plate, except for negative control. Positive (media plus bacterial cells) and negative (only media) control was used in each well and the plate was incubated at 37 C for 24 h. [23] The next day, absorbance (OD 600 ) was read, percent inhibition was determined and the lowest concentration showing bacterial inhibition was considered as MIC. Minimum bactericidal concentration (MBC) was determined by plating optically clear wells in TSA and incubated overnight at 37 C. The lowest concentration with no colonies was considered as MBC of the drug.…”