Fourier-Transform Photocurrent Spectroscopy for a fast and highly sensitive spectral characterization of organic and hybrid solar cells

• Published in: Thin solid films Vol. 516; no. 20; pp. 7135 - 7138
• Main Authors: Vandewal, K., Goris, L., Haeldermans, I., Nesládek, M., Haenen, K., Wagner, P., Manca, J.V.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Lausanne Elsevier B.V 30.08.2008; Elsevier Science
• Subjects: Applied sciences; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Dye sensitized solar cells; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport phenomena in thin films and low-dimensional structures; Energy; Exact sciences and technology; FTPS; Natural energy; Optical spectroscopy; Organic solar cells; Photoconduction and photovoltaic effects; photodielectric effects; Photovoltaic conversion; Physical radiation effects, radiation damage; Physics; Solar cells. Photoelectrochemical cells; Solar energy; Structure of solids and liquids; crystallography; FTPS; Optical spectroscopy; Dye sensitized solar cells; Organic solar cells; Solar cells; Radiation effects; Fourier transform spectroscopy; Organic dye; Ground states; Photoinduced effect; Photocurrents; Energy gap; Heterojunctions; Titanium oxide; Photoconductivity; Polymers; Charge transfer
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2007.12.056

Two modes of Fourier-Transform Photocurrent Spectroscopy (FTPS) are presented for a fast and sensitive determination of photocurrent spectra of organic and dye sensitized solar cells. Furthermore, FTPS allows to spectrally resolve sub-bandgap absorption phenomena in P3HT, in organic P3HT:PCBM bulk heterojunctions and in hybrid P3HT/TiO 2 solar cells. The sub-bandgap absorption in the P3HT:PCBM blend is dominated by a band due to the formation of a ground-state charge-transfer complex between the polymer and PCBM. In P3HT/TiO 2 junctions such a charge-transfer complex band is not observed. Long-lived light induced sub-bandgap states appear in pure P3HT and in P3HT/TiO 2 junctions after irradiation with E > 1.9 eV.