Delving Into the World of "Artificial Atoms": Ag Nanoparticles
A quantum dot or nanoparticle is a unique state of matter. Quantum dots are composed of thousands of metal atoms. These tiny crystals range in size from 1 to 100 nanometers and confine electrons on the nanometer scale. As a result these nanoparticles display unusual properties. Amphiphilic molecules have polar and non-polar regions. Such amphiphiles exhibit novel properties such as the ability to form micelles, vesicles and bilayers in a wide variety of solvents. In this investigation we seek to combine the unique properties of quantum dots with an amphiphilic passivated layer in order to form finite-size multi-particle structures. Capped with a passivation layer, the nanoparticles are easily size-selected with solvents of different polarity. Following the size selection process the particles are placed in a solution of 11-mercaptoundecanoic acid to randomly add carboxyl terminated alkanethiols to the nanoparticles. Once the synthesis is completed the particles are placed on a surface of pure water in a Langmuir-Blodgett trough in order to facilitate the orientation of polar and non-polar hemispheres through diffusion. The particles are collected as films deposited on glass and mica substrates and characterized using FTIR, Reflective IR, and Atomic Force Microscopy.
Phan, Oanh and Guerrero, Juan D., "Delving Into the World of "Artificial Atoms": Ag Nanoparticles" (2002). URC Student Scholarship.
Support provided by:NSF-REU/Chemistry