title: Efficient synthesis of triarylamine-based dyes for p-type dye-sensitized solar cells.
abstract: The class of triarylamine-based dyes has proven great potential as efficient light absorbers in inverse (p-type) dye sensitized solar cells (DSSCs). However, detailed investigation and further improvement of p-type DSSCs is strongly hindered by the fact that available synthesis routes of triarylamine-based dyes are inefficient and particularly demanding with regard to time and costs. Here, we report on an efficient synthesis strategy for triarylamine-based dyes for p-type DSSCs. A protocol for the synthesis of the dye-precursor (4-(bis(4-bromophenyl)amino)benzoic acid) is presented along with its X-ray crystal structure. The dye precursor is obtained from the commercially available 4(diphenylamino)benzaldehyde in a yield of 87% and serves as a starting point for the synthesis of various triarylamine-based dyes. Starting from the precursor we further describe a synthesis protocol for the dye 4-{bis[4'-(2,2-dicyanovinyl)-[1,1'-biphenyl]-4-yl]amino}benzoic acid (also known as dye P4) in a yield of 74%. All synthesis steps are characterized by high yields and high purities without the need for laborious purification steps and thus fulfill essential requirements for scale-up.
authors.affiliation: Department of Chemistry, Leibniz Institute of Surface Modification (IOM), Permoserstraße 15, 04318 Leipzig, Germany.|Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, University Leipzig, Linnéstraße 2, 04103 Leipzig, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Wild
authors.affiliation: Department of Chemistry, Leibniz Institute of Surface Modification (IOM), Permoserstraße 15, 04318 Leipzig, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Griebel
authors.affiliation: Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, University Leipzig, Linnéstraße 2, 04103 Leipzig, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Hajduk
authors.affiliation: Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, University Leipzig, Linnéstraße 2, 04103 Leipzig, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Friedrich
authors.affiliation: SMRI Sugarcane Biorefinery Research Chair, University of KwaZulu-Natal, College of Agriculture, Engineering and Science School of Engineering, Howard College Campus, Durban, South Africa.
authors.forename: Annegret
authors.initials: A
authors.lastname: Stark
authors.affiliation: Department of Chemistry, Leibniz Institute of Surface Modification (IOM), Permoserstraße 15, 04318 Leipzig, Germany.|Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, University Leipzig, Linnéstraße 2, 04103 Leipzig, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Abel
authors.affiliation: Department of Chemistry, Leibniz Institute of Surface Modification (IOM), Permoserstraße 15, 04318 Leipzig, Germany.
authors.forename: Katrin R
authors.initials: KR
authors.lastname: Siefermann