Unsymmetric platinum(II) bis(aryleneethynylene) complexes as photosensitizers for dye-sensitized solar cells

• Published in: Chemistry, an Asian journal Vol. 7; no. 6; p. 1426
• Main Authors: Dai, Feng-Rong, Chen, Yung-Chung, Lai, Lai-Fan, Wu, Wen-Jun, Cui, Chao-Hua, Tan, Gui-Ping, Wang, Xing-Zhu, Lin, Jiann-T'suen, Tian, He, Wong, Wai-Yeung
• Format: Journal Article
• Language: English
• Published: Germany 01.06.2012
• ISSN: 1861-471X
• DOI: 10.1002/asia.201200027

Four new unsymmetric platinum(II) bis(aryleneethynylene) derivatives have been designed and synthesized, which showed good light-harvesting capabilities for application as photosensitizers in dye-sensitized solar cells (DSSCs). The absorption, electrochemical, time-dependent density functional theory (TD-DFT), impedance spectroscopic, and photovoltaic properties of these platinum(II)-based sensitizers have been fully characterized. The optical and TD-DFT studies show that the incorporation of a strongly electron-donating group significantly enhances the absorption abilities of the complexes. The maximum absorption wavelength of these four organometallic dyes can be tuned by various structural modifications of the triphenylamine and/or thiophene electron donor, improving the light absorption range up to 650 nm. The photovoltaic performance of these dyes as photosensitizers in mesoporous TiO(2) solar cells was investigated, and a power conversion efficiency as high as 1.57% was achieved, with an open-circuit voltage of 0.59 V, short-circuit current density of 3.63 mA cm(-2), and fill factor of 0.73 under simulated AM 1.5G solar illumination.