Exploring Nanoparticles of Metal Oxides and Metal Sulfides for Efficient Reduction of Nitro Compounds

Abstract

The extensive use of nitroaromatic compounds constitutes a significant pollution issue. The nitro (-NO2) group linked to the aromatic ring renders the chemical substances refractory, allowing them to remain in the environment. The United States Environmental Protection Agency (USEPA) has classified nitrophenols, including 4-NP, as significant pollutants because they are highly toxic to living beings. To address this, we have successfully developed the nano catalysts capable of converting nitro compounds into less toxic forms, such as amines, facilitating safer waste management and pollution control. In this context, the focus of the research is to synthesize different metal oxides, metal sulfides and their composites such as NiS-NiS2, NiO, CeO2, Ag-CeO2, Fe/FexOy, Fe/FexOy/Cu, Fe/FexOy/Ni, and Fe/FexOy/Ag composites via simple, cost effective, high efficient, time and energy saving approach and studied their catalytic performance towards the reduction of 4-Nitrophenol (4-NP) into 4-Aminophenol (4-AP) as a model reaction, using sodium borohydride (NaBH4) as a reducing agent at ambient temperature. The efficiency and stability of the catalysts were evaluated. Furthermore, the versatility of the catalysts was examined by effectively reducing few more different nitroaromatic compounds. newline