2011 Theses Doctoral

Development of Photochemical Surface Modification Technique

Park, Ellane J.

This thesis will investigate two main areas of surface modification research: I. Designing a photoactive monolayer with improved photo-grafting efficiency. II. Fabrication of NP-Films via phthalimide self-assembled monolayer on glass surfaces. Concluding the thesis, I will briefly describe an outreach research project in collaboration with my GK-12 fellowship team.

In Chapter One, we will introduce nanotechnology and surface chemistry, with an emphasis on the use of monolayers for photochemical surface modification. The goal of this chapter is also to equip the reader with a comprehensive overview of common surface analytical techniques and a "how-to" analysis guide for thin films.

Chapter Two delves into the fundamentals of SAMs and thin films - the behavior and orientation of adsorbates on surfaces, particularly at air-monolayer interfaces. We discuss the importance of studying the orientation of phthalimide-undecyl-thiol molecules on gold surfaces because the photo-reactivity (i.e. accessibility) of phthalimide terminal groups is dependent on its tilt angle, surface exposure, and packing density.

One of the interesting observations includes the possibility that low packing density can potentially have higher photo-grafting efficiency. In Chapter Three, we address the challenge of applying nanoparticles to surfaces. We introduce a fairly well known photochemical surface modification technique to fabricate nanoparticle-films. By using a phthalimide self-assembled monolayer on a glass substrate, we photo-grafted organic nanoparticles to the surface and subsequently, produced a patterned NP-film. Using a photomask allows us to have spatial control and selection on NP-grafting.

Lastly, Chapter Four is a brief introduction and overview of the outreach project, studying the heavy metal intake of oysters in the New York Harbor. As a GK-12 fellow, I was given the opportunity to start a research project for the high school students and contribute to the New York Harbor Oyster restoration efforts. The research is focused on detecting heavy metal concentrations in oyster tissue and shells.