Synthesis and Characterization of Modified ZnO/GO Nanocomposites and to Study its Anti-microbial, Anti-Oxidant and Photocatalytic Activity.

Abstract

Nanocomposite materials based on metal NPs and graphene oxide (GO) have picked up growing thought for their wide expansion of potential applications in numerous materials science ranges. An efficient photocatalyst based on GO/ZnO-NCs with embedded metal NPs was successfully synthesized using the sonication method in this study. The synthesized NCs were characterized using Uv-Vis, XRD, SEM, and FTIR spectroscopy. Accordingly, the addition of 4% GO into ZnO NPs reduced its energy band gap from 2.87 eV to 2.20 eV and significantly improved their activity. Following the energy band gap reduction, the photocatalytic activity of the synthesized NCs against the degradation of MB dye significantly improved (98%) compared to the pristine ZnO NPs (For the MB containing pure ZnO-NPs the absorbance peaks were gradually decreased upon light irradiation by 91%). Among different carbon materials, graphene-based nanomaterials (GBNs) have been well explored over the past decade owing to their unique properties, such as a high surface-to volume ratio, mechanical flexibility, and a high thermal stability. The radical scavenging properties of the ZnO-NPs and ZnO/GO were evaluated through the DPPH method and showed an increasing radical scavenging activity with an increase in the NP concentrations. The NP half- maximal inhibitory concentrations (IC50) were found to be 38.38% and 51.6% for ZnO-NPs and ZnO/GO-NCs respectively. The radical scavenging activity of the synthesised NPs was determined by DPPH. It was also noted that the ZnO-NPs offer high antioxidant activity while ZnO/GO has inhibition at 80 μg/mL. The nanocomposite's antimicrobial activity was superior to that of pure ZnO-NPs and GO, indicating that incorporating GO-NPs improved the NC's antimicrobial activity. Upon the addition of a trace amount of GO material into pure ZnO-NPs, the best-ever activity improvement has been achieved to date.