Effect of Surfactants on Morphology of Gold Nanostructures Synthesized by Seedless Method

Abstract

In this thesis, effect of surfactant on the morphology of gold nanostructures has been evaluated. Gold nanostructures are synthesized by single-step seedless approach. When CTAB is used as shape directing agent, nanoparticles grow in form of nanorods. When CTAB is replaced with pluronic F-127, gold forms star like nanostructure. Effects of pH on the surface resonance bands of gold nanorods and gold nanostars have also been evaluated. Gold nanorods show red shift with decrease in the pH of growth solution while gold nanostars display blue shift with decrease in the pH of the growth solution. Tunability viz-a-viz their plasmon resonance bands and their dimensions have been achieved in both type of nanostructures by means of concentration of surfactant, volume of reducing agent and pH of growth solution.