Potential of green synthesized zero-valent iron nanoparticles for remediation of lead-contaminated water

Abstract

A bottom-up green synthesis method has been used to synthesize zero-valent iron nanoparticles taking Emblica officinalis leaf extract as reducing and stabilizing agent at ambient temperature and using FeCl3 solution as a source of iron to be reduced. UV–Vis spectroscopy, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction have confirmed the fabrication of green synthesized zero-valent iron nanoparticles. In the UV–Vis spectrum, there was a shift in absorption peak ranging between 350 and 600 nm wavelengths. Nearly, spherical zero-valent iron nanoparticles having average size of 22.6 nm were obtained through this synthesis method. Fourier transform infrared spectrum reveals that the biomolecules are responsible for the synthesis and stabilization of the green synthesized zero-valent iron nanoparticles. Diffraction peak at 2θ of 44.9° in X-ray powder diffraction spectrum illustrates the presence of pure metallic α-Fe nanoparticles with zetapotential value −26.7 mv. With the application of 20 ml l−1 concentration, green synthesized zero-valent iron nanoparticles were found very efficient for the remediation of 10, 20, 50 and 100 ppm of lead from aqueous medium within 24 h and the efficiency was positively correlated with the application time period and concentration of GZVINPs.