New Ru(II) phenanthroline complex photo sensitizers having different number of carboxyl groups for dye-sensitized solar cells

Citation
K. Hara et al., New Ru(II) phenanthroline complex photo sensitizers having different number of carboxyl groups for dye-sensitized solar cells, J PHOTOCH A, 145(1-2), 2001, pp. 117-122
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
ISSN journal
1010-6030 → ACNP
Volume
145
Issue
1-2
Year of publication
2001
Pages
117 - 122
Database
ISI
SICI code
1010-6030(20011129)145:1-2<117:NRPCPS>2.0.ZU;2-J
Abstract
We have prepared and characterized four carboxylated Ru(II) phenanthroline complexes with different number of carboxyl groups, cis-dithiocyanato bis(4 ,7-dicarboxy-1,10-phenanthroline)ruthenium(II) [Ru(dcphen)(2)(NCS)(2), DCP2 ],cis-dithiocyanato bis(4-monocarboxy-1,10-phenanthroline) ruthenium(II) [R u(mcphen)(2)(NCS)(2), MCP2], cis-dithiocyanato (4,7-dicarboxy-1,10-phenanth roline) (1,10-phenanthroline) ruthenium(H) [Ru(dcphen)(phen)(NCS)(2), DCPP] , and cis-dithiocyanato (4-monocarboxy-1,10-phenanthroline)(1,10-phenanthro line) ruthenium(H) [Ru(mcphen)(phen)(NCS)(2), MCPP], as photosensitizers fo r nanocrystalline dye-sensitized solar cells. All complexes exhibit a broad MLCT absorption band around 500 run in ethanol and an emission band around 700 nm. in ethanol-methanol (4: 1) at 77 K. The excited state lifetime of these complexes at 77 K was 1.5-2.9 mus and the oxidation potential, 0.90-1 .12 V vs. NHE, was obtained by cyclic voltammetry in solution. The best sol ar-energy-to-electric conversion efficiency under AM 1.5 irradiation was ob tained for DCPP which has two carboxyl groups on one phenanthroline ligand. The performance of photosensitizer of MCPP which has only one carboxyl gro up is lower than that for the other complexes, indicating that the number o f carboxyl groups as anchor is very important for efficient solar cell perf ormance. (C) 2001 Elsevier Science B.V. All rights reserved.