title: Branched and bulky substituted ruthenium sensitizers for dye-sensitized solar cells.
abstract: We report on the synthesis, and photovoltaic performances of four novel Ru(ii)-bipyridine heteroleptic complexes TT206-209, incorporating branched and bulkier alkyl chains compared to their linear analogues C106 and CYC-B11 previously reported. In both series, we found that dyes containing 2-methyl-hex-2-yl substitution gave better performances than 1,1-dipropylbutyl. The best overall performance over the four dyes was obtained for TT207 (CYC-B11 analogue), which contains 2-methylhex-2-yl type substitution, achieving an overall PCE of 8.5%. Furthermore, the optimization of TT207/DSSCs, with respect to the dye-uptake solvent and electrolyte composition, led to a maximum PCE of 9.1% under AM1.5 G standard conditions.
authors.affiliation: Universidad Autónoma de Madrid, Departamento de Química Orgánica, Cantoblanco, 28049 Madrid, Spain. tomas.torres@uam.es.
authors.forename: M
authors.initials: M
authors.lastname: Sánchez Carballo
authors.forename: M
authors.initials: M
authors.lastname: Urbani
authors.forename: A Kumar
authors.initials: AK
authors.lastname: Chandiran
authors.forename: D
authors.initials: D
authors.lastname: González-Rodríguez
authors.forename: P
authors.initials: P
authors.lastname: Vázquez
authors.forename: M
authors.initials: M
authors.lastname: Grätzel
authors.forename: M K
authors.initials: MK
authors.lastname: Nazeeruddin
authors.forename: T
authors.initials: T
authors.lastname: Torres