Gold Nanoshell Synthesis: The Growth of a Uniform Au Layer onto Non-Spherical PRINT Particles (2010)

Undergraduates: Ryan Orgel, Timothy Merkel

Faculty Advisor: Joseph DeSimone
Department: Chemistry

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The utilization of PRINT (Particle Replication In Non-wetting Templates) enables the creation of a large number of monodisperse nanoparticles that can be synthesized into a variety of shapes with features as small as 80nm. In particular, the synthesis of a continuous and uniform gold nanoshell onto such a particle system may give rise to a large number of applications regarding a gold shell’s unique optical properties. The creation of a PRINT nanoparticle with an even surface distribution of amine groups is employed to allow for the even attachment of gold, and the synthesis of the nanoshell occurs in two steps. First, the surface of the PRINT particle is seeded with gold by the introduction of the particle solution to a 2nm gold colloid suspension. The synthesis is complete after reduction by carbon monoxide in the presence of a gold salt. In the presence of a reducing agent and a gold salt, the seeded gold on the surface of the PRINT particles grow to form a continuous layer. This method allows for the reproducible production of a gold shell of varying thickness, as the amount of reducing agent used is directly proportional to amount of gold salt reduced. Nanoshell growth can be visually monitored using SEM.