Gold nanoparticles were produced by a citrate thermal reduction method and by a procedure involving the inclusion of reduced polyoxometalates (POMs), where phosphotungstic acid (PTA) served as the photocatalyst, reducing reagent and stabilizer for the reaction. In addition to synthesizing gold and silver nanoparticles, linear chainlike aggregates of gold nanoparticles (known as nanochains) were formed from colloidal gold in solution by adding varying amounts of cetyltrimethylammonium bromide (CTAB). The colloidal metal was successfully synthesized, as indicated by UV-Visible Spectrophotometry (UV-Vis) data, where strong gold peaks were revealed at approximately 520 nm and strong silver peaks at approximately 400 nm respectively. Single crystal alumina surfaces were soaked overnight in a solution of PTAderived gold nanoparticles or in a solution of CTAB-derived gold nanochains to determine if the colloidal gold would attach to the single crystal alumina surface. X-ray Photoelectron Spectroscopy (XPS) and Atomic Force Microscopy (AFM) were performed on the dry single crystal alumina surfaces after being submerged in their respective solutions. These data suggest that some colloidal gold remained on the alumina surface for both syntheses. However, the gold nanochains did not attach to the surface as linear chainlike aggregates, but agglomerated into clusters of colloidal gold either on the surface of the single crystal alumina, or prior to attaching to the surface of the single crystal alumina.
Brittany Szczepanik, ’09 Appleton, WI
Majors: Chemistry, English
Craig Teague, Ph.D.
Sponsor: Craig Teague