pH control as a tool for the synthesis of Ag nanoparticles (NPs) aggregates with plasmonic applications

N. CATIVA; C. E. HOPPE; I. E. DELLERBA

Mar del Plata

Simposio; XVI SIMPOSIO LATINOAMERICANO DE POLÍMEROS Y XIV CONGRESO IBEROAMERICANO DE POLÍMEROS; 2018

INTEMA (CONICET-UNMdP)

The degree of aggregation of nanoparticles (NPs)exerts an important influence on the physicochemicalproperties of a dispersion, like optical absorption andphotothermal effect1. Hence, the controlled tuning ofaggregation can be a valuable tool for the synthesis ofNPs systems with specific properties and potentialtechnological applications. The stability and degree ofaggregation of Ag NPs in a dispersion depend on thenature of the capping agent and also on the propertiesof the surrounding medium (pH, ionic strength,polarity, etc.)2. In this work, we analysed the effect ofpH and concentration on the aggregation of silver NPs,capped with a ligand bearing carboxylic acid groups, inaqueous dispersions. We then determined the effect ofthe size of these aggregates on the optical absorptionand photothermal effect of the dispersions.