Structure鈥揚roperty Relationships in Phosphonate-Derivatized, RuII Polypyridyl Dyes on Metal Oxide Surfaces in an Aqueous Environment

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• 作者：Kenneth Hanson ; M. Kyle Brennaman ; Akitaka Ito ; Hanlin Luo ; Wenjing Song ; Kelsey A. Parker ; Rudresh Ghosh ; Michael R. Norris ; Christopher R. K. Glasson ; Javier J. Concepcion ; Rene Lopez ; Thomas J. Meyer
• 刊名：The Journal of Physical Chemistry C
• 出版年：2012
• 出版时间：July 19, 2012
• 年：2012
• 卷：116
• 期：28
• 页码：14837-14847
• 全文大小：466K
• 年卷期：v.116,no.28(July 19, 2012)
• ISSN：1932-7455

文摘

The performance of dye-sensitized solar and photoelectrochemical cells is strongly dependent on the light absorption and electron transfer events at the semiconductor鈥搒mall molecule interface. These processes as well as photo/electrochemical stability are dictated not only by the properties of the chromophore and metal oxide but also by the structure of the dye molecule, the number of surface binding groups, and their mode of binding to the surface. In this article, we report the photophysical and electrochemical properties of a series of six phosphonate-derivatized [Ru(bpy)₃]²⁺ complexes in aqueous solution and bound to ZrO₂ and TiO₂ surfaces. A decrease in injection yield and cross surface electron-transfer rate with increased number of diphosphonated ligands was observed. Additional phosphonate groups for surface binding did impart increased electrochemical and photostability. All complexes exhibit similar back-electron-transfer kinetics, suggesting an electron-transfer process rate-limited by electron transport through the interior of TiO₂ to the interface. With all results considered, the ruthenium polypyridyl derivatives with one or two 4,4鈥?(PO₃H₂)₂bpy ligands provide the best balance of electron injection efficiency and stability for application in solar energy conversion devices.