Control synthesis of low aspect ratio Zn1-xAgxO nanorods using low temperature solution route: Evidence of Ag concentration dependent shape transition

Understanding the effect of doping concentration on the various properties of metal-doped ZnO nanoparticles (NPs) near the shape transition point (sphere to the rod) is essentially required for their possible applications. Given these, we have successfully synthesized spherical to rod-shaped Zn1-xAgxO employing a simple chemical route considering Ag doping with concentrations of 1, 2, and 3 mol percentage (%). Although, the shape tran-sition from spherical to rod has been triggered at doping concentration of 2 mol%, the shape transition has been found to be completed for 3 mol% generating nanorods with an aspect ratio of ~1.33. Structural, optical, and antimicrobial properties of Zn1-xAgxO NPs show significant changes at the transition concentration of Ag. The shape transition occurs mainly due to the process of synthesis and change in the surface states of the NPs in presence of excess Ag+ ions in the local environment of the nucleation sites of ZnO.