Samuel Fretz
Mentors: David McGehee and T. Daniel P. Stack
Biography
Growing up in Denver, Colorado, I’ve held a diverse set of jobs including country club caddy and bag room employee, grocery store shelf stocker, and shop hand for a Wyoming oil company. For college, I went out of state to (The) Ohio State University where I majored in chemistry and Spanish while preforming research in synthetic organic chemistry with Professor David Hart. As a fourth year graduate student in chemistry, my research interests include device fabrication and characterization and synthesizing colorful compounds (i.e. dyes). When I’m not in the lab, I enjoy skiing, hiking, video games, and most of all, sleep.
Research Summary
My project revolves around dye-sensitized solar cells (DSCs), which are a promising and relatively new technology for the development of low-cost, large-scale, energy generation. In addition, DSCs offer a unique medium in which to study fundamental physical and chemical phenomena such as charge transport, energy transfer, recombination kinetics, and chromophore structure.
In collaboration with the McGehee lab in Materials Science and Engineering, we are modifying the energy-relay dye (ERD) system for use with the copper(I) mediated azide-alkyne cycloaddition reaction, commonly known as the “click” reaction. First pioneered by the McGehee lab in 2009, the ERD system utilizes two dyes: an energy-relay dye (ERD) that absorbs blue (high-energy) light and emits red (low-energy) light and a red-light absorbing sensitizing dye (SD). The job of the ERD is to transfer the energy from the blue light to the SD via Forster Resonance Energy Transfer (FRET)
Normally, the ERD is dissolved in the electrolyte of the DSC, leaving it relatively far away from the SD, which is adsorbed to the electrode surface. The rate of FRET between isolated dyes is known to be proportional to 1/r6 where r is the separation distance. Our goal is to tether the ERD to the surface via the click reaction, thereby bringing the ERD closer to the SD and increasing the FRET and overall solar cell efficiency.