This research describes the methodology for synthesizing zinc oxide nanoparticles (ZnO-NPs). It demonstrates a unique, cost-effective, and non-toxic chemical technique for producing ZnO-NPs using the precipitation method with NaOH as reducing and capping agents. The formed nanoparticles have been characterized and analyzed using numerous techniques such as; Fluorescence emission spectroscopy (FL), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray Spectroscopy (EDX), ultraviolet-visible optical absorption (UV-Vis), Fourier transform infrared spectroscopy (FTIR), and Thermal gravimetric analysis (TGA). Also, the analytical technique X-ray diffraction studies has been used which showed that the ZnO-NPs had a Wurtzite hexagonal crystal structure with an average crystallite size of 34.27 nm. The form and the size of the synthesized ZnO-NPs have been seen in SEM and TEM photographs. Using J-image, particle size has been obtained at 13.33 nm, and the grain boundaries were all approximately spherical. Peaks in the FT-IR spectrum of the NPs indicate the presence of carboxylate (COO) and hydroxyl (O-H) functional groups. According to these findings, Zn interstitial defects are responsible for the 380 nm emission peak. Since EDX could not identify any impurities below the detection threshold, we may be sure that Zn and O are the principal components of the synthesized sample. ZnO-NPs cause an absorption band at 350.34 nm in the UV-Vis spectrum and a band gap of 3.24 eV. The catalytic activity of the synthesized ZnO nanoparticles (NPs) was evaluated by investigating their effectiveness in degrading crystal violet (CV) and methylene blue (MB) dyes, along with assessing the degradation rates. The results demonstrated a high degradation efficiency, with ZnO NPs achieving approximately 96.72 % degradation for CV and 97.169 % for MB dyes, underscoring their remarkable efficacy in the degradation process. As for antimicrobial activity assessment, the results revealed that the ZnO-NPs had negligible impact on Gram-negative bacteria, whereas they exhibited a discernible effect on Gram-positive bacteria. Additionally, it showed anti-cancer potential against colon (SW480), breast (MDA-231), and cervix (HELA) lines cells as seen by (MTT) assay. Hence, due to its simplified processes and cheaper chemicals, our synthesis technique may use in industrial settings for various applications.

The spread of organic pollutants in water spoils the environment, and among the best-known sorbents for removing organic compounds are carbonaceous materials. Sunflower seed waste (SFSW) was employed as a green and low-cost precursor to prepare carbon nanoparticles (CNPs) via pyrolysis, followed by a ball-milling process. The CNPs were treated with a nitric–sulfuric acid mixture (1:1) at 100 °C. The scanning electron microscopy (SEM) showed a particle size range of 38 to 45 nm, and the Brunauer–Emmett–Teller (BET) surface area was 162.9 m² g⁻¹. The elemental analysis was performed using energy-dispersive X-ray spectroscopy, and the functional groups on the CNPs were examined with Fourier transform infrared spectroscopy. Additionally, an X-ray diffractometer was employed to test the phase crystallinity of the prepared CNPs. The fabricated CNPs were used to adsorb ciprofloxacin (CFXN) and malachite green (MLG) from water. The experimentally obtained adsorption capacities for CFXN and MLG were 103.6 and 182.4 mg g⁻¹, respectively. The kinetic investigation implied that the adsorption of both pollutants fitted the pseudo-first-order model, and the intraparticle diffusion step controlled the process. The equilibrium findings for CFXN and MLG sorption on the CNPs followed the Langmuir and the Fredulich isotherm models, respectively. It was concluded that both pollutants spontaneously adsorbed on the CNPs, with physisorption being the likely mechanism. Additionally, the FTIR analysis of the adsorbed CFXN showed the disappearance of some functional groups, suggesting a chemisorption contribution. The CNPs showed an excellent performance in removing CFXN and MLG from groundwater and seawater samples and possessed consistent efficiency during the recycle–reuse study. The application of CNPs to treat synthetically contaminated natural water samples indicated the complete remediation of polluted water using the ball-mill-fabricated CNPs.

In this work, researchers synthesized copper–zinc oxide nanoparticles (NPs) of different shapes and sizes and tested their antibacterial and anticancer effects. The current research used a straightforward method to synthesize copper-doped zinc oxide nanoparticles (Cu-ZnO NPs). Next, the photocatalytic, antibacterial, and anticancer properties of the Cu-ZnO NPs were ascertained. Nanoparticles of Cu-doped ZnO were synthesized using co-precipitation technology. The physicochemical characterization was carried out using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet–visible (UV-Vis) and Fourier-transform infrared (FTIR) spectroscopy, and other imaging techniques. The SEM analysis confirmed that the particles observed by SEM were found to be below 100 nm in size, which aligns with the results obtained from XRD. The size histogram in the figure inset shows that the nanoparticles are mostly round and have a size range of 5 to 50 nm. The XRD diffractograms revealed the classic structure of wurtzite-phase crystalline Cu-ZnO, and the crystallite size is 26.48 nm. Differences in the principal absorption peaks between the FTIR and UV-vis spectra suggest that varying ZnO NP morphologies might lead to spectrum shifts. We used the agar diffusion method to determine how effective Cu-doped ZnO NPs were against bacteria and the MTT assay to see how well they worked against cancer. The photocatalytic disintegration capacity of Cu-doped ZnO NPs was investigated by degrading crystal violet (CV) and methylene blue (MB) dyes under ultraviolet lamp irradiation. A value of 1.32 eV was recorded for the band gap energy. All peaks conformed to those of the Zn, O, and Cu atoms, and there were no impurities, according to the EDS study. Additionally, the nanoparticles had anticancer properties, indicating that the NPs were specifically targeting cancer cells by inducing cell death. At a 100 µg/mL concentration of the synthesized Cu-doped ZnO NPs, the cell availability percentages for the SW480, MDA-231, and HeLa cell lines were 29.55, 30.15, and 28.2%, respectively. These findings support the idea that Cu-doped ZnO NPs might be a new cancer treatment. Moreover, the results show the percentage of dye degradation over different time durations. After 180 h, the degradation of CV dye reached 79.6%, while MB dye exhibited a degradation of 69.9%. Based on these findings, Cu-doped ZnO NPs have the potential to be effective photocatalysts, antibacterial agents, and cancer fighters. This bodes well for their potential applications in the fields of ecology, medicine, and industry in the future.