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Indexed by:期刊论文

Date of Publication:2010-01-01

Journal:DYES AND PIGMENTS

Included Journals:SCIE

Volume:84

Issue:1

Page Number:62-68

ISSN No.:0143-7208

Key Words:Dye-sensitized solar cells; Organic sensitizer; Phenothiazine; Tetrahydroquinoline; Triphenylamine; Electrochemical impedance spectroscopy

Abstract:A series of organic sensitizers containing identical pi-spacers and electron acceptors but different, aromatic amine electron-donating groups, were used in dye-sensitized solar cells to study the effect of the electron donating groups on device performance. The derived photophysical and photovoltaic properties, as well as density functional theory calculations, revealed that the tetrahydroquinoline dye was prone to aggregate upon the surface of titanium dioxide owing to the dye's planar structure. A 45% improvement in efficiency of a tetrahydroquinoline dye based cell was achieved when chenodeoxycholic acid was employed as co-adsorbent. However, the airscrew type of triphenylamine unit and Y type structure of the substituted phenothiazine framework suppressed dye aggregation on titanium dioxide. The efficiency of a phenothiazine dye-based cell fabricated using saturated co-adsorbent in dichloromethane was only 15% greater than that achieved in the absence of co-adsorbent. Electrochemical Impedance Spectroscopy was used to determine the interfacial charge transfer process occurring in solar cells that employed different dyes in both the absence and presence of chenodeoxycholic acid as co-adsorbent. (C) 2009 Elsevier Ltd. All rights reserved.