Facile one-pot green synthesis of Ag–Fe bimetallic nanoparticles and their catalytic capability for 4-nitrophenol reduction

Abstract

The synergy between two different metals provides a dramatic enhancement in the bimetallic nanoparticles' catalytic properties since bimetallization improves the properties associated with the presence of two individual metals. Therefore, herein, we reported the facile, seedless, one-pot green synthesis of Ag–Fe bimetallic nanoparticles via reduction process using phytochemicals present in the Salvia officinalis aqueous extract. During the Phyto-assisted nanofabrication of Ag–Fe nanoparticles, the reduction of Ag+ and Fe3+ metal ions to Ag–Fe NPs takes place according to their reduction potential. The UV–visible spectroscopic technique was initially used for the Ag–Fe nanoparticle formation in which the absorption band at 450 nm, 350 nm, and 352 nm were observed for AgNPs, FeNPs, and Ag–Fe nanoparticles, respectively. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analysis were used to investigate the size and shape of biosynthesized Ag–Fe nanoparticles, and it was revealed that the as-synthesized Ag–Fe nanoparticles are nearly spherical with an average size of 30 nm. X-ray diffraction (XRD) study was carried out to analyze the purity of the Ag–Fe nanoparticles. Fourier transform infrared spectroscopy (FTIR) analysis was performed to confirm the role of reducing and capping/stabilizing agents in the synthesis of Ag–Fe bimetallic nanoparticles. The successful biosynthesis of Ag–Fe nanoparticles was also confirmed by X-ray energy-dispersive spectrometry (EDX) analysis. Thermogravimetric analysis (TGA) was used to investigate the decomposition pattern of the Ag–Fe bimetallic nanoparticles. The catalytic behavior of as-synthesized Ag–Fe nanoparticles was investigated for the catalytic degradation of 4-nitrophenol to 4-aminophenol. The observed results revealed that Ag–Fe nanoparticles showed an efficient reduction of 4-Nitrophenol (4-NP) to 4-Aminophemol (4-AP) after 45 min of treatment.