Electronic properties of dye molecules adsorbed on anatase-titania surface for solar cell applications

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2009

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Torun, Engin

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Wide band gap metal oxides have recently become one of the most investigated materials in surface science. Among these metal oxides especially TiO2 attracts great interest, because of its wide range applications, low cost, biocompatibility and ease of analysis by all experimental techniques. The usage of TiO2 as a component in solar cell technology is one of the most investigated applications of TiO2 . The wide band gap of TiO2 renders it ine cient for isolated use in solar cells. TiO2 surface are therefore coated with a dye in order to increase e ciency. This type of solar cells are called dye sensitized solar cells . The e ciency of dye sensitized solar cells is directly related with the absorbed light portion of the entire solar spectrum by the dye molecule. Inspite of the early dyes, recent dye molcules, which are called wider wavelength response dye molecules, can absorb a larger portion of entire solar spectrum. Thus, the e ciency of dye sensitized solar cells is increased by a considerably amount. In this thesis the electronic structure of organic rings, which are the fundamental components of the dye molecules, adsorbed on anatase (001) surface is analyzed using density functionaltheory. The main goal is to obtain a trend in the electronic structure of the system as a function of increasing ring number. Electronic structure analysis is conducted through band structure and density of states calculations. Results are presented and discussed in the framework of dye sensitized solar cells theory.

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Physics.

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http://etd.lib.metu.edu.tr/upload/12610846/index.pdf
https://hdl.handle.net/11511/18718

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

E. Torun, “Electronic properties of dye molecules adsorbed on anatase-titania surface for solar cell applications,” M.S. - Master of Science, Middle East Technical University, 2009.