Interactive effect of agitation rate and oxidative etching on growth mechanisms of silver nanowires during polyol process

Abstract

In this work, the interaction between agitation rate and oxidative etching on the growth mechanisms of silver nanowires during polyol process, the most conventional applied method for metallic nanoparticles synthesis, is evaluated. It was found that the main reason for the formation of multidiameter nanowires (MDNWs) is the local accumulation of silver ions in the system, i.e. even at a low concentration of silver ions (94 mM) under the mild agitation conditions, MDNWs were producible. Moreover, it was inferred that the more stress (stemming from the high agitation) applied on the initially formed decahedron Ag particles affects the ‘re-entrant grooves opening’ process which results in the formation and growth of irregular nanostructures. A polynomial equation for tuning aspect ratio of silver nanowires using different concentration of CuCl2 solution was also proposed. Finally, based on the obtained experimental data together with the thermodynamic considerations, a growth mechanism was proposed which can promisingly be employed for describing the one-dimensional growth of silver nanowires in both surfactant-modified and surfactant-free procedures.