Abstract
The N3 dye was modified by substituting two of its protons by potassium or sodium cations. The performance and stability of dye-sensitized solar cells incorporating the new dyes were evaluated under light soaking (1000W . m(-2)) at 50 degrees C. Photocurrent measurements demonstrated that proton substitution by potassium cations rends the systemmore stable. Further characterization of the potassium-based devices was performed by electrochemical impedance spectroscopy to investigate the charge-transfer phenomena occurring at the different interfaces of the cells. Copyright (C) 2009 Luisa Andrade et al.