ACSNano11-新染料用抑制复合的方式增加电压-spiroSSDSSC.pdfVIP

JANG ET AL. VOL. 5 ’ NO. 10 ’ 8267–8274 ’ 2011 8267 September 20, 2011 C 2011 American Chemical Society Voltage-Enhancement Mechanisms of an Organic Dye in High Open-Circuit Voltage Solid-State Dye-Sensitized Solar Cells Song-Rim Jang,?,?, ) Kai Zhu,?, ) Min Jae Ko,? Kyungkon Kim,? Chulhee Kim,§ Nam-Gyu Park,?,^,* and Arthur J. Frank?,* ?Chemical and Materials Science Center, National Renewable Energy Laboratory (NREL), Golden, Colorado 80401, United States, ?Solar Cell Research Center, Materials Science and Technology Division, Korea Institute of Science and Technology (KIST), Seoul 136-791, Korea, §Department of Polymer Science and Engineering, Inha University, Incheon 402-751, Korea, and ^School of Chemical Engineering and Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Korea. )These authors contributed equally to this work. M esoscopic dye-sensitized solar cells (DSSCs) have received much attention as inexpensive and re- markably efficient solar devices.1 The most extensively studied DSSCs consist of a monolayer of a ruthenium bipyridyl dye adsorbed to the surface of a thin nanocrys- talline TiO2 film supported on a transparent conducting oxide (TCO) glass substrate. The TiO2 crystallites of the film are in contact with a liquid redox electrolyte containing iodide and triiodide ions that serve as a redox relay. The Ru complex is typically attached to the oxide surface via carboxyl pendant groups on the bipyridyl ligand. Photocurrent is generated when visible or near-infrared light absorption by the sensiti- zer leads to electron injection into the con- duction band of TiO2. Sunlight-to-electrical conversion efficiencies of over 11% at full sunlight (AM1.5 solar irradiance) have been reported for DSSCs incorporating Ru com- plexes for photon harvesting.2,3 Recently, metal-free organic dyes have attracted atten- tion owing to their potential for having high- er absorption coefficients, synthetically more tunable spectral response, larger abun