Facile synthesis and characterization of chitosan/zinc oxide nanocomposite for enhanced antibacterial and photocatalytic activity

In this report, chitosan/zinc oxide (CS/ZnO) nanocomposite was synthesized using Sida acuta and assessed their antibacterial and photocatalytic properties. The formation of CS/ZnO nanocomposite was preliminary confirmed by colour change and UV-visible spectroscopy. The crystalline peaks related to CS and ZnO in CS/ZnO nano composite were demonstrated by XRD. Morphological analysis through FE-SEM and TEM showed a rod like appearance for ZnO NPs and agglomerated grains with rod shaped morphology was observed for the CS/ZnO nanocomposite. The peaks around 400-800 cm(-1) in the IR spectrum of nanocomposite indicated the vibrations of metal-oxygen (Zn-O), whereas bands at 1659 cm-1 and 1546 cm(-1) indicated the presence of amine groups, which confirms the CS in the synthesized CS/ZnO nanocomposite. The CS/ZnO nanocomposite exhibited remarkable growth inhibition activity against B. subtilis and E. coli with 22 +/- 0.3 and 16.5 +/- 0.5 mm zone of inhibitions. In addition, CS/ZnO nanocomposite treated cotton fabrics also exhibited antibacterial activity against B. subtilis and E. coli. Furthermore, the ZnO NPs and nanocomposite showed time depended photo degradation activity and revealed 76% and 91% decomposition of CR under sunlight irradiation. In conclusion, our study revealed that the functionalization of biopolymer CS to the inorganic ZnO enhances the bio and catalytic properties.

Automated summary

In this study, CS/ZnO nanocomposite with enhanced antibacterial and photocatalytic properties was successfully synthesized using Sida acuta. The nanocomposite showed remarkable growth inhibition activity against B. subtilis and E. coli, while also exhibiting time-dependent photo degradation activity under sunlight irradiation. Overall, the functionalization of biopolymer CS with inorganic ZnO enhanced the bio and catalytic properties of the nanocomposite.