Robust green synthetic approach for the production of iron oxide nanorods and its potential environmental and cytotoxicity applications

Recent progress in green and biopolymer based photocatalysts for the abatement of aquatic pollutants

Enormous research studies on the abatement of anthropogenic aquatic pollutants including organic dyes, pesticides, cosmetics, antibiotics and inorganic species by using varieties of semiconductor photocatalysts have been reported in recent decades. Besides, many of these photocatalysts suffer in real applications owing to their high production cost and low stability. In many cases, the photocatalysts themselves are being considered as secondary pollutants. To eliminate these drawbacks, the green synthesized photocatalysts and the use of biopolymers as photocatalyst supports are considered in recent years. In this context, recent developments in green synthesized metals, metal oxides, other metal compounds, and carbon based photocatalysts in water purification are critically reviewed. Furthermore, the pivotal role of biopolymers including chitin, chitosan, cellulose, natural gum, hydroxyapatite, alginate in photocatalytic removal of aquatic pollutants is comprehensively reviewed. The presence of functional groups, electron trapping ability, biocompatibility, natural occurrence, and low production cost are the major reasons for using biopolymers in photocatalysis. Finally, the summary and conclusion are presented along with existing challenges in this research area.

Facile one pot microwave-assisted green synthesis of Fe2O3/Ag nanocomposites by phytoreduction: Potential application as sunlight-driven photocatalyst, antibacterial and anticancer agent

Herein, we report a one-pot microwave assisted method to prepare an efficient Fe₂O₃/Ag nanocomposites (NCs) using Aloe vera (A. vera) gel extract as a mild, safe, renewable and active stabilizer without any harmful reagent. The advanced characterization techniques including XRD, FT-IR, UV-DRS, PL, TGA, SEM-EDX, TEM, DLS, Elemental mapping, VSM and BET were applied to analyze the morphology and structure of the prepared Fe₂O₃/Ag NCs. The results exhibited that the Fe₂O₃/Ag NCs was successfully synthesized by greener route. Furthermore, these bio-reduced Fe₂O₃/Ag NCs was tested for its catalytic degradation toward methylene blue (MB) as a model contaminant and exhibited outstanding photocatalytic degradation efficiency with 88.2% removal rate in 140 min. It was worth pointing out that the Fe₂O₃/Ag nanoparticles facilitated the charge transportation and inhibit the charge recombination of an electron in the conduction band. Additionally, the prepared Fe₂O₃/Ag NCs was studied for their in-vitro antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria and anticancer properties against A549 cell lines (human lung cancer). The biological results of this study demonstrated that A. vera gel extract derived Fe₂O₃/Ag NCs showed significant inhibition properties against bacterial strains and also capable of achieving superior action against A549 cancer cell lines.