Copper oxide nanoparticles (CuO NPs) have garnered profound interest for their promising roles in catalysis and optoelectronics owing to their distinct structural and crystallographic characteristics. Highly crystalline monoclinic CuO NPs were synthesized and systematically characterized using X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and transmission electron microscopy (TEM), accompanied by selected area electron diffraction (SAED). XRD combined with Rietveld refinement confirmed single-phase formation with 100% phase purity, while SAED displayed sharp diffraction rings predominantly corresponding to the (002) and (111) planes, verifying structural uniformity and crystallographic alignment. Rietveld refinement using the whole powder pattern fitting (WPPF) method yielded refined lattice parameters of a= 4.6966 Å, b= 3.4323 Å, and c= 5.1293 Å, with a unit cell volume of 81.559 ų. The average crystallite size was estimated to be 39.144 nm using the Scherrer equation. The material exhibited a moderate atomic packing factor of 61.4%, underscoring its compact and stable crystal framework. TEM image revealed spherical, non-agglomerated NPs with an average diameter of 81.55 nm. DLS analysis indicated a hydrodynamic diameter of 452.3 nm and a zeta potential of + 38.51 mV, suggesting excellent colloidal stability. UV-Vis spectroscopy revealed a well-defined absorption edge, and the calculated bandgap of 5.08 eV suggests strong potential for applications in high-energy optoelectronics. The atomic mass percentage of copper is 79.20% and oxygen 20.80% revealed by EDS. The remanent mass magnetization of the synthesized CuO NPs, measured by VSM, was 0.000988991327703501. The structural, magnetic, and functional evaluations validate the excellent quality of the synthesized CuO NPs. The synthesized CuO NPs exhibited selective antibacterial activity against the Gram-positive bacterium Staphylococcus aureus (10.5 ± 0.5 mm zone) while showing minimal effect on Gram-negative bacteria, indicating their potential as targeted antibacterial agents. • Monoclinic crystal phase 100% and degree of crystallinity 51.253%. • Lattice parameters of a= 4.6966 Å, b= 3.4323 Å, and c= 5.1293 Å, with a unit cell volume of 81.559 ų. • TEM imagery revealed spherical with an average diameter of 81.55 nm. • Calculated d-spacings 0.2322 nm (111) plane and 0.1773 nm (112) plane in SAED. • Antibacterial activity against Staphylococcus Aureus . • Remanent mass magnetization 0.000988991327703501 emu/g in VSM.
Alam et al. (2026) studied this question.