Dye-Sensitized Solar Cells Based on Organic Sensitizers with Different Conjugated Linkers: Furan, Bifuran, Thiophene, Bithiophene, Selenophene, and Biselenophene

Abstract

Six organic dyes with different conjugated linkers such as furan, bifuran, thiophene, bithiophene, selenophene, and biselenophene have been prepared in combination with the dihexyloxy-substituted triphenylamine donor and the cyanoacrylic acid acceptor. In conjunction with an acetonitrile-based electrolyte and a solvent-free ionic liquid electrolyte, these dyes exhibit 6.88−7.77% and 6.39−7.00% efficiencies, respectively. We have demonstrated that furan and selenophene can be employed as building blocks of sensitizers in stable solar cells for the first time. We have also studied the influence of heteroatoms on photocurrents and photovoltages with the aid of quantum calculations and transient photoelectrical decay measurements. Temperature-dependent electrical impedance experiments have shown that a relatively low external quantum efficiency of the dye with biselenophene linker is not related to the charge collection yield in the case of an acetonitrile electrolyte.

The Role of the π Linker in Donor–π–Acceptor Organic Dyes for High‐Performance Sensitized Solar Cells

“…In addition, the role of linker length is crucial in tuning the dye spectrum. [24,25,27,31,36] These and other related issues are further discussed below.…”

Phenoxazine Dyes for Dye‐Sensitized Solar Cells: Relationship Between Molecular Structure and Electron Lifetime

“…[26,27,38] By extending the conjugation with a furan ring linker (MP08) the absorption spectrum can be redshifted. [39,40] The introduction of an additional electron donor in the 7-position on the POZ (MP03, MP05) will increase the energy levels, mostly affecting the HOMO, which will be lifted towards a more negative value to generate a bathochromic shift. The influence of insulating alkyl chains has been shown to be beneficial for the performance of the cell due to decreased aggregation, increased solubility, and surface protection that will depress the recombination of the injected electron with the oxidized dye or the redox species in the electrolyte.…”

Indolizine‐Based Donors as Organic Sensitizer Components for Dye‐Sensitized Solar Cells

“…The TPA-based dyes L1 (identical to CQ1 ) and C213 (a C1 analogue) give similar values for this stretch (1683 cm −1 for L1 , [ 14 ] 1682 cm −1 for C213 , Table 2 ). [ 15 ] An indoline-based dye gave only a slightly smaller carbonyl vibrational frequency value (1680 cm −1 ). [ 16 ] In comparison, indolizine-based dyes gave an average value of 1646 cm −1 , which is a signifi cantly lower wavenumber (≈35 cm −1 ) than the other donors examined.…”