posted on 2015-07-15, 00:00authored byChi-Lun Mai, Thomas Moehl, Chi-Hung Hsieh, Jean-David Décoppet, Shaik M. Zakeeruddin, Michael Grätzel, Chen-Yu Yeh
Three
novel efficient donor–acceptor porphyrins, MH1–MH3,
with a pyridine-type acceptor and anchoring group were synthesized
and their optical, electrochemical, and photovoltaic properties investigated.
Replacing the commonly used 4-carboxyphenyl anchoring group with 2-carboxypyridine,
2-pyridone, and pyridine did not significantly change the absorption
and electrochemical properties of the porphyrin dyes. These new porphyrin
dyes MH show power conversion efficiencies of 8.3%, 8.5%, and 8.2%,
which are comparable to that of the benchmark YD2-o-C8 (η = 8.25%) under similar conditions. It was demonstrated
that 2-carboxypyridine is an efficient and stable anchoring group
as MH1 and showed better cell performance and long-term stability
than YD2-o-C8 under light soaking conditions.