Impact of Weak Organic Acids on Precipitation of Poly(acrylic acid) Stabilized Silver Nanoparticles; an Electrochemical Approach

Owing to recent developments in the field of silver nanoparticle (AgNP) based conductive inks for inkjet printing, there is a growing demand for implementation of novel synthetic routes. This study presents a synthesis of silver colloid with an average particle diameter of less than 3 nm. AgNPs were obtained by a chemical reduction method, using hydrazine as a reducing agent, and poly(acrylic acid), (PAA), as a grain-stabilizing agent. Synthesis was provided using highly concentrated aqueous solutions. To obtain PAA-coated silver nanopowder, weak organic acids were introduced as precipitation agents. The main goal of this work was to study the impact of various organic precipitants on nanosurface-adsorbed polyacid for enhanced ink stability, by implementing electrochemical techniques. Cyclic voltammetry and electrochemical impedance spectroscopy were the main methods in describing all steps of the procedure - from preliminary experiments to whole system characterization. For a comprehensive study of the nanoink suspension, dynamic light scattering (DLS) and electrokinetic potential measurements were carried out. The obtained results show, through a very apparent decrement in anodic current responses, the influence of different organic acid precipitants on nanoink destabilization.