Home > Research > Publications & Outputs > Pyridinium p-DSSC Dyes: An old acceptor learns ...

Associated organisational unit

View graph of relations

Pyridinium p-DSSC Dyes: An old acceptor learns new tricks

Research output: Contribution to Journal/MagazineJournal articlepeer-review

Published
  • Anil Marri
  • Fiona Black
  • John Mallows
  • Elizabeth Gibson
  • John Fielden
Close
<mark>Journal publication date</mark>1/06/2019
<mark>Journal</mark>Dyes and Pigments
Volume165
Number of pages10
Pages (from-to)508-517
Publication StatusPublished
<mark>Original language</mark>English

Abstract

A family of six (five new) thiophenyl bridged triarylamine-donor based dyes with pyridine anchoring groups have been synthesized and studied as sensitizers for the p-type dye-sensitized solar cell (p-DSSC). They comprise bis-dicyano acceptor systems with a single pyridyl binder incorporated directly into the triarylamine (1), or separated by a phenyl group (2); a mono-dicyano with two phenyl pyridine binders (3); and respective homologues 4 to 6 with pyridinium acceptors. In all cases, compared to their dicyano counterparts, the pyridinium based dyes have higher extinction coefficients and smaller HOMO-LUMO gaps that give broader spectrum absorption. Thus, despite lower dye uptake, devices based on pyridiniums 4 and 6 have identical power conversion efficiencies (η) to the equivalent dicyano systems 1 and 3. However, the best performing device (η = 0.06%) is based on the known bis-acceptor dicyano system 2, as the large size and double positive charge of 5 leads to a substantial disadvantage in loading on NiO. Absorbed-photon-to-current efficiencies for 5 are competitive with or higher than those of 2, implying a better per dye performance consistent with the absorption profile, and DFT calculations suggesting better charge separation. Thus, pyridiniums may provide a new, and easily accessible high performance acceptor for p-DSSC dyes, but are likely better paired with anionic binding groups such as carboxylates.

Bibliographic note

Open access status of this article is currently being determined by RIN. In the meantime it is uploaded with publishers green open access embargo period of 24 months.