Frederickk Sudbury, University of Utah
Physical Sciences
Triphenylphosphine stabilized gold nanoparticles were synthesized using a method developed previously by the Jennifer Shumaker-Parry group. Aminated silica colloids were obtained from the Ilya Zharov group. The gold nanoparticles were adhered to the silica colloids using a method developed for another purpose by the Zharov group. The presence of the particles on the silica colloids was confirmed using both scanning and transmission electron microscopy. The catalytic activity of the gold nanoparticles both with and without adhesion was investigated. It was found that free nanoparticles had significant catalytic activity, in agreement with previous research. Gold nanoparticles attached to silica colloids do not seem to exhibit the same level of catalytic activity as the free particles. It was also found that not all the gold nanoparticles adhered to the surface of the silica particles. Experiments were conducted to determine if there was a critical concentration of silica colloids that would allow for high levels of adhesion of the gold nanoparticles. It was found that only by adding a significant excess of silica colloids to the solution can all the gold nanoparticles be removed from the solution. It was also found that the silica can be saturated with gold nanoparticles by including a small amount of them in a very concentrated gold nanoparticle solution. Further studies for functionalization of the silica colloids and the ability to physically isolate the silica with gold nanoparticles from free nanoparticles are currently in progress.