Dye-sensitized solar cells based on Fe N-heterocyclic carbene photosensitizers with improved rod-like push-pull functionality

Abstract

Iron-based photosensitizers for dye-sensitized solar cells with a rod-like push–pull design. Solar cell performance was limited by ultrafast (sub-ps) recombination, but yielded better performance than the homoleptic parent photosensitizer.

Solar energy conversion using first row d-block metal coordination compound sensitizers and redox mediators

“…The parameters in Table 10 are the average values for three cells. Interestingly, the performances of DSCs with 78 were lower when the co-adsorbent cheno was added to the dye bath ( Table 10 ), 280 and this observation appears to be consistent with the competition between dye and cheno reported by Lindh et al 271 However, the electrochemical impedance spectroscopic response was more strongly influenced by the immersion time in the dye bath than by the addition of cheno. 280 …”

“…The first is optimization of the electrolyte composition. Until recently, 271 NHC iron( ii )-based DSCs have only incorporated the I 3 − /I − redox mediator, and a commercial electrolyte (AN50) was used in the initial report from Gros. 269 AN50 comprises I 2 (0.05 M), LiI (0.1 M), the ionic liquid 1,2-dimethyl-3-propylimidazolium iodide (DMPII, Scheme 26 ) and TBP (0.5 M) in MeCN.…”

“…Reproducibility of the DSC parameters was checked by measuring four cells, and ranges of values are given in Table 10 . 271 …”

“…In 2021, Wärnmark and coworkers reported that use of the [Co(bpy) 3 ] 3+ /[Co(bpy) 3 ] 2+ redox mediator with dye 72 leads to a drastic decrease in J SC (<0.2 mA cm −2 ), most probably due to significantly greater recombination of electrons with the oxidized form of the redox couple in the case of cobalt. 271 …”

“…The DSC parameters for 82 and 83 in Table 10 are the best cells from sets of four for which performances were reproducible. 271 …”