Developing a cheap, stable and effective photocatalyst is necessary for remediation of persistent organic pollutants. To address this challenge, we proposed a unique interfacial engineering technique and proper bandgap matching strategy to synthesize MWCNTs/ZnO/Chitosan ternary nanocomposite for effective photocatalytic application. The features of the prepared samples were determined by FESEM, TEM, EDX, elemental mapping, AFM, FT-IR, XRD, UV–Vis spectroscopy and BET surface analysis. The obtained results showed successful fabrication of synthesized nanocomposites with enhanced surface area. Degradation effect of nanostructures on methylene blue (MB) and antibacterial activity against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and Bacillus subtilis (B. subtilis) pathogenic strains were investigated. The proposed photocatalytic mechanism illustrated the electron transfer facilitated by MWCNTs/ZnO/Chitosan structure which results in spatial separation of electron–hole pairs. Compared with ZnO and ZnO/Chitosan, the prepared MWCNTs/ZnO/Chitosan ternary nanocomposite showed high usage of UV illumination and superior separation of photogenerated electron–hole pairs. MWCNTs/ZnO/Chitosan illustrated 86.26% adsorption rate and outstanding increased photocatalytic activity on MB degradation efficiency of 98.76% after 20 min. Stability of photocatalyst reached from 98.76% initial decolorization to 85% at the fourth cycle. In addition, the ternary nanocomposite also exhibited remarkable bactericidal activity against gram-positive (S. aureus) and (B. subtilis) and gram-negative (E. coli) bacteria strains. Due to the obtained results, the prepared nanocomposite would be an efficient candidate photocatalyst with antibacterial properties.

Using density functional theory, the mechanism of adsorption of 2-chlorophenol from water in the presence of γ-Fe 2 O 3 nanoparticles was investigated. Fe 2 O 3 nanoparticles were modelled using Fe 6 (OH) 18 (H 2 O) 6 ring clusters. 2-chlorophenol can coordinate to the γ-Fe 2 O 3 nanoparticles via its own OH or Cl groups. The process produces two intermediates which will be converted into final products through two pathways (Cl pathway and OH pathway). The activation energy and activation Gibbs free energy of the two pathways have been calculated and compared with each other. It was found that the OH pathway is under thermodynamic control and the C1 pathway is under kinetic control. All of the calculations were performed using a hybrid density functional method (B3LYP) in the solution phase (PCM model).

Development of light-harvesting properties and inhibition of photogenerated charge carrier recombination are of paramount significance in the photocatalytic process. In the present work, we described the synthesis of core–shell heterostructures, which are composed of titanium oxide (TiO 2 ) and cerium oxide (CeO 2 ) deposited on a reduced graphene oxide (rGO) surface as a conductive substrate. Following the synthesis of ternary rGO-CeO 2 @TiO 2 and rGO-TiO 2 @CeO 2 nanostructures, their photocatalytic activity was investigated toward the degradation of rhodamine B dye as an organic pollutant under UV light irradiation. The obtained structures were characterized with high-resolution transmission electron microscopy, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, Brunauer–Emmett–Teller, X-ray photoelectron spectroscopy surface analysis, and UV–Vis spectroscopy. Various parameters including pH, catalyst dosage, temperature, and contact time were studied for photocatalysis optimization. Heterostructures showed considerable advantages because of their high surface area and superior photocatalytic performance. In contrast, rGO-CeO 2 @TiO 2 showed the highest photocatalytic activity, which is attributed to the more effective electron–hole separation and quick suppression of charge recombination at core–shell phases. A biological assay of the prepared heterostructure was performed to determine the cytotoxicity against breast cancer cells (MCF-7) and demonstrated a very low survival rate at 7.65% of cells at the 17.5 mg mL –1 concentration of applied photocatalyst.

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The present study aims to prepare and And Characterization of zein nanofibers with simvastatin-loaded in it by electrospinning method using a polymeric matrix prepared from zein solution containing simvastatin antibiotics. The physical, cellular properties and drug release kinetics of the fibers were studied. Fiber formation was investigated by implementing a scanning electron microscope (SEM). The SEM images show a uniform network bead-free fiber structure created from the 1.5% simvastatin/zeinsolution. The viscosity of the 1.5% simvastatin/zein mixture increased to 0.402 P due to the presence of drug in zein solution. Also, the presence of the indicative peaks associated with simvastatin in the Fourier transform infrared (FTIR) spectra of the samples containing the drug, verifies the existence of the drug on the polymeric base of zein/polyethylene oxide (PEO). Also, around 53.887% of the loaded drug was released in the first 12 h of the release kinetics assay and the results of the MTT assay shows reduction in the number of live cells in the test sample. In conclusion, zein nanofibers containing simvastatin drug were found to be potential biodegradable polymers that can find application in bone tissue repair.