1. Research proposal Elena Khon The development and optimizing the performance of high efficient prototype solar cells 1

2. Problem: Energy crisis I propose work that will target: the development of colloidal chemistries for growing semiconductor nanocrystals onto substrate-bound oxides, elucidating the nature of interfacial charge transfer and heterojunction stoichiometry though ultrafast optical spectroscopy, and advanced electron microscopy imaging techniques, optimizing the performance of prototype solar cells comprising fabricated composite nanomaterials. 2

3. Highest efficiency of nano-composit solar cells known nowadays is 5.1% 3

4. Charge Separation in Nano-composites Valence band Conduction and valence band Conduction band 4

5. Schematics of photovoltaic device hetero- epitaxial NC/oxide nano-composites 5

6. Electronic energy level of each material layer in a NC-sensitized solar cell comprising a solid hole conductor. Vertical bars represent size-dependent band edge energies for several semiconductor NCs. 6

7. Primary goal and expected result The increasing of the efficiency of photovoltaic device achieved through understanding of growth kinetics of each nanocrystal/oxide system, the development of large-scale and well- controlled synthesis of durable nanostructures, and optimization of device performance 7

8. References Pattantyus-Abraham, A. G.; Kramer, I. J.; Barkhouse, A. R.; Wang, X.; Konstantos, G.; Debnath, R.; Levina, L.; Raabe, I.; Nazeeruddin, M. K.; Gratzel, M.; Sargent, E. H.: Depleted-Heterojunction Colloidal Quantum Dot Solar Cells. ACS Nano 2010, 4, 3374. Grätzel, M.: Conversion of Sunlight to Electric Power by Nanocrystalline Dye-Sensitized Solar Cells. J. Photochem. Photobiol. A 2004, 164, 3. Schmidt-Mende, L.; Grätzel, M.: TiO2 Pore-Filling and Its Effect on the Efficiency of Solid-State Dye-Sensitized Solar Cells. Thin Solid Films 2006, 500, 296. Acharya, K. P.; Hewa-Kasakarage, N. N.; O’Conner, T.; Nemitz, I.; Klinkova, A.; Anzenbacher, P.; Zamkov, M.: Nanocrystal-Sensitized Solar Cells Based on Hot-Injection Growth of PbS Sensitizer Onto Mesoporous TiO2 Films. Submitted, 2010. Casavola, M.; Buonsanti, R.; Caputo, G.; Cozzoli, P. D.: Colloidal Strategies for Preparing Oxide-Based Hybrid Nanocrystals. Eur. J. Inorg. Chem. 2008, 837. 8

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