Plant-Based Copper Oxide Nanoparticles; Biosynthesis, Characterization, Antibacterial Activity, Tanning Wastewater Treatment, and Heavy Metals Sorption

Abstract

Herein, the aqueous extract of Portulaca oleracea has been used as a safe, cheap, eco-friendly, and applicable scale-up method to bio-fabricate copper oxide nanoparticles (CuO-NPs). The character of CuO-NPs were determined using UV-vis spectroscopy, Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Transmission electron microscopy (TEM), Energy dispersive X-ray(EDX), Dynamic light scattering (DLS), and zeta potential. Spherical and crystalline CuO-NPs with a size range of 5–30 nm at a maximum surface plasmon resonance of 275 nm were successfully fabricated. The main components of the green-synthesized particles were Cu and O with weight percentages of 49.92 and 28.45%, respectively. A Zeta-potential value of −24.6 mV was recorded for CuO-NPs, indicating their high stability. The plant-based CuO-NPs showed promising antimicrobial and catalytic activity in a dose-dependent manner. Results showed that the synthesized CuO-NPs had the efficacy to inhibit the growth of pathogens Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans with low MIC values in the ranges of 6.25–25 µg/mL. The highest decolorization percentages of tanning wastewater were attained under sunlight irradiation conditions at a concentration of 2.0 mg/mL after 200 min with percentages of 88.6 ± 1.5% compared to those which were recorded under dark conditions (70.3 ± 1.2%). The physicochemical parameters of tanning wastewater including total suspended solids (TSS), total dissolved solids (TDS), chemical oxygen demand (COD), biological oxygen demand (BOD), and conductivity under optimum conditions were significantly decreased with percentages of 95.2, 86.7, 91.4, 87.2, and 97.2%, respectively. Interestingly, the heavy metals including cobalt (Co), lead (Pb), nickel (Ni), cadmium (Cd), and chromium (Cr (VI)) decreased with percentages of 73.2, 80.8, 72.4, 64.4, and 91.4%, respectively, after treatment of tanning wastewater with CuO-NPs under optimum conditions. Overall, the plant-synthesized CuO-NPs that have antimicrobial and catalytic activities are considered a promising nano-catalyst and environmentally beneficial to wastewater treatment.

Bio-capped multifunctional CuO nanoparticles via Knautia arvensis for dye removal, antibacterial and antifungal efficiency, and molecular docking

“…The peak at 800 cm −1 can be corresponded to the bending of aromatic C-H. The peaks at 600 and 595 cm −1 can be attributed to the pure and successful formation of CuO as reported previously [20,23]. By these results, the presence of CuONPs, polysaccharides, amines, amides (groups I and II), alcohols, ethers, carbohydrates, nucleic acids were verified by the FT-IR analysis.…”

Tanning Wastewater Sterilization in the Dark and Sunlight Using Psidium guajava Leaf-Derived Copper Oxide Nanoparticles and Their Characteristics

“…According to Wang et al, declining the removal of COD rates throughout sewage treatment at both low and high CuO NP amounts was not of statistical significance. According to the previous study, the elimination amount of COD utilizing 0.1 mg/L CuO NPs was 93.21%, but when its concentration was increased to 20 mg/L, the figure dropped to 88.25% …”

“…Superoxides ( • O 2– ) and hydrogen peroxide ( • OOH) formed when energized e – in the CB interacted with oxygen, while unstable hydroxide radicals ( • OH) were created when h + reacted with water. , In sewage, such unstable molecules react with impurities and dyes, degrading them to carbon dioxide, water, and other tiny ions. According to the information gathered, the physical and chemical traits of sun exposure wastewater have been investigated at an amount of 1.6 mg/mL, following 210 min of exposure to sunlight illnesses, which was identified as the most effective condition for the decolorization process …”

“…According to the information gathered, the physical and chemical traits of sun exposure wastewater have been investigated at an amount of 1.6 mg/mL, following 210 min of exposure to sunlight illnesses, which was identified as the most effective condition for the decolorization process. 36 Compared to natural wastewater, the effluent variables pH, COD, BOD, TSS, TDS, and resistivity were assessed under ideal conditions. The range of contaminants found in tannery effluent depends on the dimension of the tanning box, the substances employed, the finished goods, and the volume of water utilized throughout the tanning procedure.…”

Enhancing the Photocatalytic Degradation of Methylene Blue with Graphene Oxide-Encapsulated g-C3N4/ZnO Ternary Composites

“…Another technique for disinfecting wastewater with nanomaterials is facilitated by harnessing the catalytic processes, which is the stimulation of several chemical reactions . Metallic nanoparticles like silver and gold can stimulate the degradation of wastewater pollutants like microorganisms and organic substances . Additionally, photocatalysis, as we previously discussed, is a different method of water purification that may be applied by using semiconductor nanoparticles, including silicone dioxide, titanium dioxide, and zinc oxide as a photocatalyst, which is more effective and demands fewer doses of ultraviolet light.…”