Abstract

Non-aqueous microemulsions of the ternary system AOT (surfactant), isooctane and ethylene glycol may be composed of spherical or cylindrical aggregates at specific proportions. Using this type of microemulsions it is possible to synthesize silver nanoparticles using silver nitrate as source of the metallic ions.Ethylene glycol serves at the same time as solvent for the silver nitrate and reducing agent of silver ions.The silver nanoparticles synthesized in the spherical aggregates are discrete (average particle size of 10 nm) and do not align. On the other hand, the nanoparticles obtained in cylindrical structures (birefringent phases) align forming linear and ordered arrays. The microemulsions were characterized with optical microscopy between crossed polarizers whereas discrete and linear arrays of silver nanoparticles were observed under transmission electron microscopy to determine their shape and size; HRTEM was used to confirm the crystal structure of the silver nanoparticles and EDS was used for their chemical analysis.