Size controlled synthesis of silver nanoparticles: a comparison of modified Turkevich and BRUST methods

In the present investigation, silver nanoparticles were synthesized and a comparative analysis was performed of modified Turkevich and BRUST methods. Silver nitrate precursor was reduced by trisodium citrate dihydrate and ascorbic acid was used as a surfactant. Based on Turkevich and BRUST methods, the process variables, i.e., temperature, reducing agent concentration, stirring speed, mode of injecting reducing agent/precursor to large excess volume of either precursor/reducing agent were studied. The size of the particles was preliminarily ascertained by DLS studies and it was found that modified BRUST method yielded silver nanoparticles with average particle size of 25 nm, while modified Turkevich method furnished nanoparticles with average particle size of 15 nm. The silver nanoparticles were characterized by employing the UV/visible, Zeta sizer, scanning electron microscopy (SEM) and energy dispersive microscopy (EDX) techniques. Results revealed that the silver nanoparticles size can be controlled by optimizing the conditions of modified Turkevich and BRUST methods.