CuO nanoparticles: green combustion synthesis, applications to antioxidant, photocatalytic and sensor studies.

The use of metal oxide nanoparticles for heterogeneous photodegradation is a prominent method for the removal of organic dyes from water resources. Compared to conventional approaches to treat polluted water, it is a more preferable method because of its environmental friendliness, low cost, and no requirement of extreme temperature and pressure. Among all the nanoparticles, CuO is a prominent material. Therefore, this study reports on the biogenic preparation of CuO nanoparticles by adopting a combustion method and pod extract as fuel. The synthesized nanoparticles were characterized through X-ray diffraction spectroscopy to confirm the crystallinity of CuO; the surface morphology of the material was studied using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) and the purity of the material was confirmed by energy dispersive X-ray spectroscopy. The degradation efficiency of CuO nanoparticles towards methylene blue dye, a model pollutant present in water resources, was assessed and found to be 97% after 90 minutes of light exposure. The synthesized CuO nanoparticles were also examined for antioxidant and electrochemical sensing studies using cyclic voltammetry. Results showed that CuO nanoparticles function as a strong antioxidant and are a very effective electrochemical sensor.