Enhanced structural, dielectric, and antibacterial properties of Sr(1−x)CuxO2 nanoparticles synthesized via sol–gel method

Abstract

In this study, we investigated the preparation, characterization, and antibacterial properties of strontium oxide (SrO) nanoparticles doped with different ratios of copper oxide (CuO) (1, 2, 3, and 4 mol.%). The SrO@CuO nanoparticles were synthesized using the sol–gel method, which is known for producing highly homogeneous and pure nanoparticles in a versatile and cost-effective manner. The study investigates the impact of CuO on the growth of the nanoparticles and their antibacterial and dielectric properties. Several techniques including X-ray diffraction, transmission electron microscopy, FTIR, and dielectric spectroscopy were used to analyze the morphological, crystallographic, and electric properties of the SrO@CuO nanoparticles. The dielectric properties of the nanoparticles were performed to study the polarization at the interface, energy loss (tan ε), and conductivity from 0.1 Hz to 20 MHz. Koop's two-layer model was suggested to explain the changes in impedance with frequency. The model suggests that the samples contain well-directing grains detached by some insulating grain boundary. As the frequency increases, the impedance decreases, and the interfacial polarization goes down. This happens when the dielectric dipoles stop following the applied reciprocating electric field. The antibacterial effects of CuO nanoparticles on Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis were also observed. The samples showed antibacterial efficacy. The study found that the concentration of CuO significantly affects the structure, spectroscopic properties, and antibacterial efficacy of the CuO nanoparticles. The results indicate that SrO@CuO nanoparticles are appropriate for energy storage, recording media, microwaves, and antimicrobial agents.