Oligothiophene dye-sensitized solar cells

Abstract

We scrutinize the energetic and kinetic interplays in oligothiophene dye-sensitized solar cells via analyzing electrical impedance as well as transient emission and absorption spectroscopies.

Extended π‐Bridge in Organic Dye‐Sensitized Solar Cells: the Longer, the Better?

“…[ 20 ] Organic molecules with different dipole moments and polarizability (these parameters are listed in Supporting Information Table S1) were found to modify the electronic properties of the semiconductors. [ 21 ] The same phenomenon has been observed by Liu et al, [ 11 ] when the number of thiophene units in the dye π -spacer was increased.…”

Probing the regeneration process of triphenylamine-based organic dyes in dye-sensitized solar cells

“…The decrease of electron transfer rates with the extension of p-conjugated linker mainly comes from the increased activation free energies and the decreased electronic coupling energies. The longer half-reaction time for dye regeneration implies the slower electron transfer rate, and the calculated rates for dye regeneration are qualitatively consistent with the experimental observation [17]. The halfreaction time for T3 dye is 21 ms, which is about 2.5 times longer than the value of 8 ms for T1 [18].…”

“…Since the di(3-hexylthiophene) of C239 is more flexible than N-hexyldithienopyrrole of C241 and dihexylcyclopentadithiophene of C218, the rigidity of the p-linker is enhanced from C239 to C241 and C218. All the seven selected dyes have been successfully synthesized and applied in DSSCs by Wang's group [17,20].…”

Electron‐Acceptor‐Dependent Light Absorption, Excited‐State Relaxation, and Charge Generation in Triphenylamine Dye‐Sensitized Solar Cells

“…[68] A modelocked Ti:sapphire laser (Tsunami, Spectra Physics) pumped by a Nd:YVO4 laser (Millennia Pro s-Series, Spectra Physics) was used as a source of a regenerative amplifier (RGA, Spitfire, Spectra Physics) to generate 3.7 mJ, 130 fs pulses at 800 nm, which were split into two parts at a ratio of 9:1 with a beam splitter. [70] Device fabrication and characterization: A bilayer titania film (4.2+5.0 mm in thickness) was coated on a precleaned FTO conducting glass (Nippon Sheet Glass, Solar, 4.0 mm in thickness) by screen-printing as the negative electrode of DSCs. The pump light was focused on a rotating sample through a phase-locked chopper.…”