Uncovering the consequences of Ag1+ on nano-structural, magneto-optical, antibacterial, and antifungal response of nickel oxide particles

Abstract

Metal oxide nanoparticles existing in transition metal series have intensely earned high research interest among material scientists by virtue of their dispersive magnetic nature desirable for antimicrobial action. Herein, we report the unsubstituted and silver (Ag) doped nickel oxide nanoparticles with varying dopant concentrations AgxNi1−xO (x = 0.00, 0.05, 0.10, and 0.15 M) prepared via flexible sol–gel citrate route at optimum temperature. The well-resolved prominent peaks from X-ray Diffraction (XRD) pattern confirmed the micro-structural attributes of NiO particles and the corresponding crystallite size decreases from 25.67 to 10.93 nm (nm) upon doping. The bandgap energy evaluated from the Tauc plot traced an increasing trend from 2.48 to 3.09 eV affirming the blue shift reasoned with the Burstein Moss phenomenon. Scanning Electron Microscopy (SEM) analysis portrayed the formation of spherical nanoparticles and the particle size was calculated. The phase purity and the chemical composition of nanoparticles were elucidated from Energy Dispersive X-ray (EDX) spectra which endorse only the presence of Ni, Ag, and O metals. Fourier Transform Infra-Red (FTIR) spectroscopy analysis operated in an IR vibrational spectral span confirms the functional group matrix. Dielectric constant and loss of doped nanoparticles were discussed where the loss decreases with increasing dopant concentration. Saturation magnetization (Ms) and coercivity (Hc) were calculated from Vibrating Sample Magnetometer (VSM) studies where Ms perform a declining tendency from 39.96 to 2.86 emu/g which is favorable in the construction of antennas and memory storage equipment. In addition, the nanoparticles were tested against different bacterial and fungal organisms to examine their antimicrobial activity wherein the high concentration (Ag0.15Ni0.85O) doped nanoparticles exhibited a higher antimicrobial response.