Fabrication of cobalt oxide nanosheets using Withania somnifera root extract for degradation of organic pollutants

Abstract

In today’s scenario, material science emerges as pivotal players, as it is an emerging and fast-growing interdisciplinary field. Nanomaterials are increasingly popular among researchers due to their unique physicochemical properties and multifaceted applications. Recently, researchers are exploring more sustainable approaches for the synthesis of nanomaterials due to its numerous advantages. In this context, present investigation reports an approach for the synthesis of cobalt oxide nanosheets (Co3O4 NSs). This approach leverages environmentally friendly and sustainable methods, minimizing the use of hazardous chemicals and reducing energy consumption. Hence it involved Withania somnifera (ashwagandha) root extract as a greener reductant as well as stabilizing agent. The synthesized Co3O4 NSs were thoroughly analyzed using various techniques, including ultraviolet-visible (UV–vis) spectroscopy, fourier-transform infrared spectroscopy (FTIR), powder x-ray diffraction (PXRD), and field emission scanning electron microscopy (FE-SEM). A sharp absorption peak at 252 nm with a tail towards higher wavelength reveal the formation of Co3O4 NSs. The diffraction pattern reveals a face centered cubic structure of Co3O4 NSs. Morphological studies confirmed the substantial surface area of Co3O4 NSs which enable us to perform the catalytic degradation of azo dye, i.e., methyl orange. It provides that 10 mg of Co3O4 NSs is sufficient to degrade a 10 ppm aqueous methyl orange solution by 75.82 % in the dark and by 96.12 % under sunlight exposure. Thus, this study offers an excellent pathway for the synthesis of Co3O4 NSs and demonstrates their potential as a promising material for future catalytic applications.

Keywords

• Cobalt oxide nanosheets
• Withania somnifera
• Green synthesis
• Dye degradation
• Methyl orange