SYNTHESIS AND CHARACTERIZATION OF COPPER OXIDE NANOPARTICLES USING THEOBROMA CACAO FOR THE ADSORPTION OF METHYLENE BLUE DYE FROM SYTHENTIC WASTE WATER
Greatness OluwoleNanaomaterials can be synthesized using several conventional techniques such as co- precipitation, micro-emulsion, sol–gel method, electrospray synthesis, laser ablation, and hydrothermal processing. Though, these approaches are often energy-demanding, environmentally hazardous, and produce cytotoxic byproducts. Green nanotechnology, on the other hand, offers a sustainable alternative by utilizing plant extracts rich in
phytochemicals as natural reducing and stabilizing agents. In the present study, copper oxide nanoparticles (CuO NPs) were synthesized using Theobroma cacao leaf
extract, which acted as both a reducing and stabilizing agent. The synthesized CuO
NPs were characterized using UV–Vis spectroscopy, X-ray diffraction (XRD), Scanning Electron Microscopy coupled with energy-dispersive X-ray analysis (SEM– EDX), and Fourier-transform infrared spectroscopy (FTIR). UV–Vis spectra
displayed a broad absorption band at 405 nm, confirming nanoparticle formation. XRD analysis revealed the crystalline structure of CuO with high purity, showing
diffraction peaks at 2θ = 7.8°, 20.1°, 38.1°, 44.9°, 57.9°, and 68.0°, corresponding to
the (110), (111), (200), (202), (113), and (311) planes of monoclinic CuO, respectively. FTIR spectra showed characteristic O–H and C=O stretching vibrations, attributed to phytochemicals from the cacao extract, which were responsible for
nanoparticle stabilization. SEM analysis revealed spherical morphology with
moderate aggregation and EDX analysis confirmed copper and oxygen as the
dominant elements.
Keywords: Theobroma cacao, Copper Oxide nanoparticles, Green Synthesis.Notes
The green synthesis of copper oxide nanoparticles (CuO NPs) using Theobroma cacao leaf extract holds significant local importance, particularly in regions like Nigeria and other cocoa-producing areas where cacao plants are abundant. This approach adds value to agricultural waste, as cacao leaves—often discarded—can be utilized as a cost-effective, renewable resource for nanoparticle production.
Moreover, the synthesized CuO NPs have promising applications in addressing local environmental challenges such as wastewater contamination from textile and dye industries. Their potential use in adsorbing methylene blue dye demonstrates a sustainable solution for water purification, contributing to improved public health and environmental safety.
Beyond environmental remediation, locally produced CuO NPs can find applications in antimicrobial coatings, sensors, and catalytic processes—encouraging local innovation, reducing dependence on imported materials, and promoting eco-friendly nanotechnology practices that align with green chemistry principles.