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.