Professor Kenneth Hanson
Department of Chemistry & Biochemistry
Florida State University
Harnessing Molecular Photon Upconversion Using Self-Assembled Multilayers on Metal Oxide Surfaces
Photon upconversion—combining two or more low energy photons to generate a higher energy excited state—is an intriguing strategy for increasing the maximum theoretical solar cell efficiencies from 33% to greater than 43%. In this presentation we will recount our work using self-assembled multilayers of sensitizer and acceptor molecules on nanocrystalline metal oxide films as a unique structural motif for facilitating molecular photon upconversion via triplet-triplet annihilation (TTA-UC) and directly extracting charge from the upconverted state. Under light intensities as low as ambient solar flux we demonstrate a more than four-fold increase in the short circuit current relative to the sum of the sensitizer and acceptor monolayer devices. We will discuss the dynamics events during TTA-UC, limitations of the current film, and the role of interfacial structure in dictating the performance.
Kenneth Hanson
Kenneth Hanson received a B.S. in Chemistry from Saint Cloud State University (2005), his Ph.D. from the University of Southern California (2010), followed by an appointment as a postdoctoral scholar at the University of North Carolina at Chapel Hill (2010–2013). His independent research career began in 2013 at Florida State University as a member of the Department of Chemistry & Biochemistry and is affiliated with the Materials Science & Engineering program. His current research interests include the design, synthesis, and characterization of photoactive molecules/materials with particular emphasis on manipulating energy and electron-transfer dynamics at organic–inorganic interfaces using multilayer self- assembly.
331 Smith Hall