Optimization of green synthesis of silver nanoparticles using Response Surface Method (RSM)

Abstract

This study is aimed at investigating the effect of synthesis parameters such as temperature, pH, volume of precursor and volume of extract on the crystal size of silver nanoparticles (AgNPs) synthesized via plant extract of Piptadeniastrum africanum (African Oak) using 24 factorial experimental design. The synthesized nanoparticles were characterized by X-ray Diffraction (XRD) and High Resolution Scanning Electron Spectroscopy (HRSEM) fitted with Energy Dispersive Spectroscopy (EDS). The optimum values of the synthesis parameters were found to be: pH 8, reaction temperature 35 °C, the ratio of the volume of extract to the volume of precursor was kept at 1:10 while silver nitrate (AgNO3)aq solution was maintained at 1 mM concentration. The HRSEM and XRD analysis showed that the morphology of the nanoparticles is spherical with an average crystal size of 20-25 nm.