Molecules 2012, 17(2), 2188-2218; doi:10.3390/molecules17022188
Review

Mechanisms of Suppression and Enhancement of Photocurrent/Conversion Efficiency in Dye-Sensitized Solar-Cells Using Carotenoid and Chlorophyll Derivatives as Sensitizers

Received: 10 December 2011; in revised form: 14 February 2012 / Accepted: 15 February 2012 / Published: 22 February 2012
(This article belongs to the Special Issue Carotenoids)
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract: The mechanisms of suppression and enhancement of photocurrent/conversion efficiency (performance) in dye-sensitized solar cells, using carotenoid and chlorophyll derivatives as sensitizers, were compared systematically. The key factor to enhance the performance was found to be how to minimize interaction among the excited-state dye-sensitizer(s). In a set of retinoic-acid (RA) and carotenoic-acid (CA) sensitizers, having n conjugated double bonds, CA7 gave rise to the highest performance, which was reduced toward RA5 and CA13. The former was ascribed to the generation of triplet and the resultant singlet-triplet annihilation reaction, while the latter, to the intrinsic electron injection efficiency. In a set of shorter polyene sensitizers having different polarizabilities, the one with the highest polarizability (the highest trend of aggregate formation) exhibited the higher performance toward the lower dye concentration and the lower light intensity, contrary to our expectation. This is ascribed to a decrease in the singlet-triplet annihilation reaction. The performance of cosensitization, by a pair of pheophorbide sensitizers without and with the central metal, Mg or Zn, was enhanced by the light absorption (complementary rather than competitive), the transition-dipole moments (orthogonal rather than parallel) and by the pathways of electron injection (energetically independent rather than interactive).
Keywords: dye-sensitized solar cells; carotenoid and chlorophyll derivatives; singlet-triplet annihilation
PDF Full-text Download PDF Full-Text [2252 KB, uploaded 18 June 2014 19:44 CEST]

Export to BibTeX |
EndNote


MDPI and ACS Style

Koyama, Y.; Kakitani, Y.; Nagae, H. Mechanisms of Suppression and Enhancement of Photocurrent/Conversion Efficiency in Dye-Sensitized Solar-Cells Using Carotenoid and Chlorophyll Derivatives as Sensitizers. Molecules 2012, 17, 2188-2218.

AMA Style

Koyama Y, Kakitani Y, Nagae H. Mechanisms of Suppression and Enhancement of Photocurrent/Conversion Efficiency in Dye-Sensitized Solar-Cells Using Carotenoid and Chlorophyll Derivatives as Sensitizers. Molecules. 2012; 17(2):2188-2218.

Chicago/Turabian Style

Koyama, Yasushi; Kakitani, Yoshinori; Nagae, Hiroyoshi. 2012. "Mechanisms of Suppression and Enhancement of Photocurrent/Conversion Efficiency in Dye-Sensitized Solar-Cells Using Carotenoid and Chlorophyll Derivatives as Sensitizers." Molecules 17, no. 2: 2188-2218.

Molecules EISSN 1420-3049 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert