Biosynthesis of gold nanowires using sugar beet pulp

Abstract

Sugar beet pulp was used as reductor and capping agent for the synthesis of gold nanowires. Reduction of tetrachloroaurate with sugar beet pulp is a simple, room temperature and environmentally friendly method. Polysaccharides and proteins are involved in the bioreduction and synthesis of nanoparticles. Different pH and molar concentration ratios of HAuCl4 were studied for the synthesis of gold nanowires. The formation of nanowires was induced by both basic mediums, due to the competence between biomolecules and hydroxide ions, and high concentrations of gold ions, because of the lack of capping agent to stabilize the preliminary nanoparticles formed that stick together producing wire-like nanostructures instead of nanospheres. This method allowed the synthesis of crystalline gold nanowires in the absence of a surfactant or polymer to direct nanoparticle growth, and without externally added seed crystallites. The synthesis of other metallic nanostructures such as silver and platinum could be achieved following a similar procedure.