RESUMO
Manganese powder with a suitable potential (, -1.19 V) has never been investigated for the reduction of Au3+ (, 1.00 V). In this study, we have utilized and low pH dependent for the polyethylene glycol stabilized gold nanoprism synthesis by reducing AuCl-4 in the presence of thiol terminated polyethylene glycol as the stabilizing agent. The synthetic methodology for gold nanoprisms has been optimized by pH and Cl- ion combination. Time dependent absorbance studies have been conducted to demonstrate the role of various reaction parameters such as the stabilizing agent, HCl concentration, temperature, and Mn metal. The synthesized gold nanoprism has been further utilized as a seed for nucleic acid and selected amino acid mediated edge and surface growth, respectively.
RESUMO
Green synthesis of gold-zinc oxide (Au-ZnO) nanocomposite was successfully attempted under organic solvent-free conditions at room temperature. Prolonged stirring of the reaction mixture introduced crystallinity in the ZnO phase of Au-ZnO nanocomposites. Luminescence properties were observed in these crystalline Au-ZnO nanocomposites due to in situ embedding of gold nanoparticles (AuNP) of 5-6 nm diameter on the surface. This efficient strategy involved the reduction of Au(III) by Zn(0) powder in aqueous medium, where sodium citrate (NaCt) was the stabilizing agent. Reaction time and variation of reagent concentrations were investigated to control the Au:Zn ratio within the nanocomposites. The reaction with the least amount of NaCt for a long duration resulted in Au-ZnO/Zn(OH)2 nanocomposite. X-ray photoelectron spectroscopy (XPS) confirmed the formation of Zn(OH)2 and ZnO in the same nanocomposite. These nanocomposites were reconnoitered as bioimaging materials in human cells and applied for visible light-induced photodegradation of rhodamine-B dye.
