Facile and eco-benign synthesis of Au@Fe2O3 nanocomposite: Efficient photocatalytic, antibacterial and antioxidant agent.

The development of eco-benign experimental procedures for the synthesis of nanomaterials is a fundamental developing branch of green nanotechnology. In this paper, green synthetic route was followed to synthesize novel Au@Fe2O3nanocomposite using Citrus sinensis fruit extract as a reducing and stabilizing agent. The as synthesized Au@Fe2O3nanocomposite was successfully characterized by UV-visible spectroscopy, X-ray diffraction (XRD), Scanning electron microscope (SEM), Energy-dispersive X-ray (EDX), Fourier transform infrared (FT1R) spectrophotometry and Zeta potential. UV-vis spectroscopy showed two SPR peaks for Fe2O3 and coated Au at 290 and 520 nm respectively. XRD confirmed the crystallinity of Au@Fe2O3. Au@Fe2O3 nanocomposite showed better antioxidant activity to effectively scavenge DPPH. The Au@Fe2O3 has been also tested for antibacterial activity which showed an effective antibacterial activity against multi drug resistant E.coli and Bacillus subtilis. Furthermore, Au@Fe2O3 also demonstrated better photo catalytic activity for methylene blue (MB) degradation. We proposed that the existence of organic acids (citric acids) also played a significant role in the stabilization of Au@Fe2O3, and plant (Citrus sinensis Var Kozan yerly) containing such component may be more effective for the green synthesis of Au@Fe2O3 nanocomposite. The findings of this study prove the overwhelming therapeutic and photocatalytic potential of bio-inspired Au@Fe2O3nanocomposite which can be a novel candidate for the effective remediation of microbes and toxic organic pollutants.