@article {45493,
	title = {Effect and position of spiro-bipropylenedioxythiophene pi-spacer in donor-pi-spacer-acceptor dyes for dye-sensitized solar cell},
	journal = {Dyes and Pigments},
	volume = {161},
	year = {2019},
	month = {FEB},
	pages = {313-323},
	type = {Article},
	abstract = {<p>Improper orientation and self-assembly of dyes on TiO2 surface are the main disadvantages at the dye-TiO2 interface that governs both charge injection and dye regeneration processes. In this report, a series of homo spiro-dimeric donor-pi-spacer-acceptor (D-pi-A) dyes based on bithiophene and terthiophene spacers with two-anchoring group containing dyes, TT1, T1T, TT1T were designed and synthesized by Pd-catalyzed successive Suzuki coupling followed by direct arylation reactions. The position of branching centre in TT1 and T1T was systematically varied, where the spiro unit was placed near and away from the anchoring carboxylic acid unit, respectively. The dimeric spiro-dye T1T showed device performance, which is 1.6 fold higher than its structural isomeric analogue TT1, of 3.9\% with a V-oc and J(sc) of 0.593 V and 9.09 mA/cm2, respectively, whereas for the isomeric analogue TT1 a device performance of 2.45\% (V-oc of 0.568 V and J(sc) of 6.25 mA/cm2) under simulated 1 Sun (100 mW/cm2) condition. The improved Voc for the dye T1T compared to TT1 dye was ascribed to the dipole moment exerted by the dyes on TiO2 surface. Further the PCE of 4.16\% (V-oc 0.589 V, J(sc) 9.79 mA/cm2 respectively) maximum was observed, when an extra thiophene unit was inserted in between the donor and pi-spacer in dye TT1T. The shifting the position of branching spiroBiProDOT pi-spacer makes an impact on the device performance by synergistically enhancing both Voc and Jsc.</p>},
	keywords = {CDCA, D-pi-A Spiro dye, Dye aggregation, dye-sensitized solar cell, spiroBiProDOT spacer},
	issn = {0143-7208},
	doi = {10.1016/j.dyepig.2018.09.056},
	author = {Sil, Manik Chandra and Kavungathodi, Munavvar Fairoos Mele and Nithyanandhan, Jayaraj}
}
@article {46421,
	title = {pi-Extended cis-configured unsynimetrical squaraine dyes for dye-sensitized solar cells: panchromatic response},
	journal = {ACS Applied Energy Materials},
	volume = {2},
	year = {2019},
	month = {DEC},
	pages = {8464-8472},
	type = {Article},
	abstract = {<p>{Light absorbing sensitizer is the heart of the third generation photovoltaic technologies such as dye sensitized solar cells. Despite possessing large extinction coefficients for the metal-free organic dyes, the light harvesting efficiency is limited with the narrow absorption 20 profile in either visible or NIR regions of the solar spectrum. Though monolayer formation of organic sensitizers on semiconducting metal oxide surface leads to dye-dye interaction that leads to broadening the absorption profile, the contribution of the aggregated state to the power conversion process is found out to be poor. Here, we have engineered far-red active pi-extended cis-configured unsymmetrical squaraine dyes with carboxylic acid and cycnoacetic acid as anchoring groups with controlled aggregation and panchromatic light absorption by including the steric and electronic factors. The presence of sp(3)-C (out-of-plane) and N-alkyl (in-plane) groups played an important role in modulating the assembly of the dyes on the TiO2 electrode; the cis-squaraine unit helps to extend the conjugation in the NIR region besides enhancing the visible transition and the incident photon-to-current conversion efficiency profile that showed the importance of anchoring groups for the panchromatic response. Dye PSQ10 showed solar-to electric conversion with an onset of 850 nm with the device performance of 7.0\% (V-oc = 0.581 V, J(sc) = 17.06 mA/cm(2)</p>
},
	keywords = {cis-squaraine dyes, Dye aggregation, Dye-sensitized solar cells, extended far-red absorption, panchromatic response},
	issn = {2574-0962},
	doi = {10.1021/acsaem.9b01341},
	author = {Punitharasu, Vellimalai and Kavungathodi, Munavvar Fairoos Mele and Singh, Ambarish Kumar and Nithyanandhan, Jayaraj}
}
