Synthesis of Highly Dispersed Gold and Silver Nanoparticles Anchored on Surfactant Intercalated Montmorillonite

Abstract

Gold and silver nanoparticles anchored on surfactant intercalated montmorillonite were prepared by two methodologies. In the first case, gold and silver nanoparticles were synthesized by reduction of gold and silver salt in hexadecyltrimethylammonium bromide (HDTA) and dioctadecyldimethylammonium chloride (DODA), followed by exchange of HDTA and DODA solution containing gold and silver nanoparticles into montmorillonite (MMT). In second case, HDTA and DODA with gold and silver salt was exchanged with MMT, and then reduced to obtain gold and silver nanoparticles. The particle size of gold and silver varies with the path of reduction as well as type of surfactant used for the modification of MMT. Gold and silver nanoparticles synthesized using quaternary ammonium salt with two long alkyl chain resulted into finer particles than a single long alkyl chain. The present study demonstrates the effect of reduction path, type of surfactants, and concentration of gold and silver on the particle size of gold and silver nanoparticles anchored on organoclay. Gold and silver nanoparticles supported organoclay were characterized by High resolution transmission electron microscopy (HRTEM), powdered X-ray diffraction (PXRD) and Inductive coupled plasma-atomic emission spectroscopy (ICP-AES).