The objective of this research is to achieve photon to electron energy conversion efficiencies in nanostructured donor-acceptor photovoltaics that exceed the seemingly intractable constraint imposed by the donor-acceptor molecular orbital energy level structure. This is a serious limitation that restricts the theoretical power efficiency of organic molecular, conjugated polymer, metal-oxide and quantum dot photovoltaics. The approach is to acquire an integrated deposition system that will be used to fabricate nanostructured photovoltaics consisting of multi-step energy gradients and optically-thin interstitial layers.
Intellectual Merit: The instrumentation will enable a cross-disciplinary team from three institutions in the Five College area to focus their efforts toward making lasting contributions to the field of next-generation photovoltaics. New high-performance organic molecular and polymer semiconductors with unique frontier orbital tunability will be synthesized to serve as energy gradients. Electric force microscopy and time-resolved spectroscopy will be employed to uncover the elusive fundamental physics of charge dynamics at the donor-acceptor interface. Excessive leakage currents that often plague nanostructured devices will be identified using a non-destructive thermoreflectance imaging technique.
Broader Impact: Nanostructured donor-acceptor photovoltaics offer tremendous processing advantages over conventional photovoltaics, potentially affording large-area manufacturability, unparalleled low cost, flexibility (even stretch ability), and dramatically lighter-weight module arrays, all at unprecedented scales. Fabrication and analysis of inorganic/organic optoelectronic devices offer a wealth of learning opportunities for students, both to explore fundamental science and to gain hands-on experience that often encourages undergraduates to continue with careers in the sciences.
