Hydroquinone Synthesis of Silver Nanoparticles: A Simple Model Reaction To Understand the Factors That Determine Their Nucleation and Growth

A simple experimental model system based on the reaction between silver(I) and a hydroquinone has been used to investigate the synthesis of silver nanoparticles (NPs) in aqueous media. Progressive nucleation and autocatalytic surface growth were found to be the relevant processes that control the morphology. The effect of synthetic parameters (such as the chemical nature of the metallic precursor, hydroquinone concentration, stabilization agents, and ligands) on the NP nucleation and growth are discussed on the basis of the optical properties, morphological characterization, and electrodynamics calculations. A very important dependence of the final morphology of the NPs on the procedure of mixing of reactants was found to be connected to the nature of the metallic precursor. Ammonia solutions containing strong stabilization agents were demonstrated to help to control shape and size by quenching autocatalytic surface growth.