Investigations on structural, textural, optical and antimicrobial properties of solvothermally tailored Ni-doped ZnO nanoparticles

Nickel-doped Zinc Oxide (Ni-ZnO) nanocomposites have a great potential in tackling of the antimicrobial resistance. In the current research, pure ZnO and a series of Ni-ZnO (1 to 10% Ni) nanoparticles are fabricated successfully via. a solvothermal route. The X-ray diffraction spectra ascertained the hexagonal wurtzite structure with effective incorporation of Ni²⁺evidenced through lattice parameter shifts and microstrain variations. The FT-IR spectra showed maintained Zn–O bonding and decreased surface hydroxyl groups on Ni doping. The SEM and TEM images revealed evolution in morphology from rod-shaped ZnO to spherical nanoparticles of Ni-ZnO. The UV-Vis spectroscopy exhibited the increasing absorbance and decreasing bandgap from 3.05 eV to 2.95 eV. The XPS established the presence of Zn²⁺, Ni²⁺, and oxygen without secondary phases. The antimicrobial screening of the materials unveiled good activity against Staphylococcus aureus and moderate against the Candida albicans , with no action on Escherichia coli bacteria. These findings validate ZnO-based nanocomposites as viable agents for biomedical and pharmaceutical applications.