Rumex hastatus mediated green synthesis of AgNPs: An efficient nanocatalyst and colorimetric probe for Cu2+

Abstract

The biogenic synthesis of silver nanoparticles (AgNPs) using plant extract has developed an economical and environment-friendly method. In this study, we report the synthesis, characterization, and potential applications of Rumex Hastatus stabilized silver nanoparticle (Rh-AgNPs) using a green chemistry approach. Several parameters were optimized for the synthesis of Rh-AgNPs, including the influence of temperature, reaction duration, extract concentration, and silver nitrate (AgNO3) concentration. Rh-AgNPs were characterized by ultra-violet visible spectroscopy (UV–Vis) scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) and Zetasizer analysis. TEM, SEM, AFM and Zetasizer investigation indicated that most of the particles are almost spherical with a size range around 50–60 nm. The photocatalytic activity of Rumex hastatus stabilized silver nanoparticles (Rh-AgNPs) was determined through sodium borohydride (NaBH4) mediated reduction of 4-nitrophenol and degradation of hazardous organic dye, namely methyl orange (MO). Rh-AgNPs showed excellent catalytic activity for reducing 4-nitrophenol to 4-aminophenol and for the degradation of methyl orange dye. The recognition potential of Rh-AgNPs was examined using UV–visible spectroscopy and colorimetric assay, which demonstrated that Rh-AgNPs based nanoparticles could be used as an efficient colorimetric sensor for the recognition of Cu2+. The addition of Cu2+ produces a colorimetric response, and the yellow color of Rh-AgNPs turns out to be radish brown within five minutes, which the naked eye can easily visualize. Rh-AgNPs were successfully used for the detection of Cu2+ in tap water samples.