Leaf extract-mediated synthesis of Mn-doped CuO nanoparticles for antimicrobial, antioxidant and photocatalytic applications

The objective of the present investigation is the synthesis, characterization, antimicrobial, antioxidant and photocatalytic activities of pure and Mn (3%, 5% and 7%)-doped CuO nanoparticles fabricated using Annona muricata leaf extract. The obtained nanopowders were analysed by XRD, FTIR, XPS, HRTEM, SEM, EDX, SAED and UV–visible studies. XRD pattern reveals the monoclinic structure of CuO nanoparticles. FTIR was used to identify the functional groups present in the nanoparticles. XPS measurements confirm the binding energy, chemical state and chemical composition of Mn dopant ions in host CuO nanoparticles. The morphology of CuO nanoparticles is affected by Mn doping concentration, according to SEM and HRTEM analysis. EDX spectra reveal the purity and homogeneity of the sample. The optical properties of nanoparticles were investigated by UV–visible spectroscopy. The antimicrobial potential of pure and Mn-doped CuO nanoparticles was tested against pathogenic bacterial and fungal strains. Also, CuO nanoparticle exhibits respectable antioxidant activities. Furthermore, the photocatalytic effects of samples were tested for the MB dye degradation. Overall, this study shows that green synthesized pure and Mn-doped CuO nanoparticles can be used in biomedical as well as waste water management applications.