Green synthesis of CuO, ZnO and CuO/ZnO nanoparticles using Annona glabra leaf extract for antioxidant, antibacterial and photocatalytic activities

Nanoparticles play a vital role in biomedicine and water purification applications, but the synthesis of nano-particles often undergoes a cost-effectiveness, unsafety, and energy consuming drawbacks. A plant extract-mediated production approach of nanoparticles without inclusion of toxic chemical not only satisfies strict re-quirements of green chemistry but also solve such problems. Herein, we performed a bio-mediated fabrication of CuONPs, ZnONPs, CuO/ZnONPs70:30, CuO/ZnONPs50:50, and CuO/ZnONPs30:70 using Annona glabra L. leaf extract. XRD analysis revealed average particle sizes of 18.70 +/- 2.65 nm (CuONPs), 12.90 +/- 1.18 nm (ZnONPs), 22.46 +/- 2.78 nm (CuO/ZnONPs70:30), 24.99 +/- 4.87 nm (CuO/ZnONPs50:50), and 27.21 +/- 3.45 nm (CuO/ ZnONPs30:70). In term of sunlight-driven photocatalytic activity, ZnONPs and CuO/ZnONPs30:70 exhibited higher methylene blue degradation efficiencies than that of CuONPs, CuO/ZnONPs70:30, and CuO/ZnONPs50:50. The same trend of antibacterial activity of these biosynthesized nanoparticles was also observed against various bacteria. Additionally, the nanoparticles showed strong antioxidant potential through DPPH radical scavenging. The obtained results indicated that the synthesized CuONPs, ZnONPs and CuO/ZnONPs can be promising photocatalytic, antibacterial, and antioxidant agents.