The abundant and sustained nature of sunlight leaves little doubt that solar cell technology will play a pivotal role in future clean energy strategies. It is for this reason that considerable efforts are underway to improve upon current solar cell designs that can only convert less than a third of sun light into electricity. The research team seeks significantly increased conversion efficiencies through a new, low cost, next generation solar cell that utilizes previously unharnessed low energy sun light. Achieving this goal requires an understanding of how molecules assemble and interact on solar cell surfaces, how fast each step in the light-to-electricity conversion process unfolds, and the barriers preventing solar cell materials from creating more energy from available light. Integrated into the project are outreach activities that engage the online community with research-related photos, videos, and stories via blogs and other social media. Complementing this online effort is also an event called Ask a Scientist where several scientists engage local community members in casual conversations about science during a once-a-month art, music, and entertainment festival.
Photon upconversion, combining two or more low energy photons to generate a higher energy excited state, is an intriguing strategy to harness low energy light, circumvent the Shockley-Queisser limit, and increase the maximum theoretical solar cell efficiency from 33% to above 45%. However, achieving efficient upconversion under ambient solar intensities and incorporating this process directly into a solar cell remains challenging. This CAREER project utilizes multilayer self-assembly on inorganic surfaces to manipulate energy and electron transfer dynamics at an interface and directly harness upconversion in a solar cell. This project also combines electrochemical and spectroscopic techniques to gain a fundamental understanding of the rate and efficiency limiting energy and electron transfer processes in assemblies at metal oxide interfaces. The incorporation of new sensitizer and acceptor molecules into the bilayer film is necessary to achieve efficient upconversion under low energy, solar irradiation. Complementing this research effort are a number of outreach activities that target individuals from many different educational, socio-economic, and racial/ethnic backgrounds.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
