@article {48934,
	title = {Aniline and indoline donors based far-red active unsymmetrical squaraine dyes for dye sensitized solar cells},
	journal = {Chemphotochem},
	volume = {8},
	year = {2024},
	month = {FEB},
	type = {Article},
	abstract = {<p>In dye-sensitized solar cells (DSSC), controlling the dye-aggregation on the metal-oxide surface by appending the alkyl groups around the donor or pi-spacer unit of the dye is a potential approach to enhance DSSC efficiency. Further, rigidification of the dye structures by cyclization modulates the photophysical properties of the sensitizer. Here a series of donor-acceptor-donor (D-A-D) type far-red active unsymmetrical squaraine dyes (SQA) have been designed and synthesized, where N,N-dimethylaniline, methylated- and branched-indoline have been used as donor units. These dyes showed absorption between 629-654 nm (lambda max) with the molar extinction coefficient of 1.49-1.94x105 M-1 cm-1. Systematic enhancements in DSSC device efficiency have been observed due to the cyclization and alkyl-groups incorporation in this set of dyes which were further enhanced with the addition of chenodeoxycholic acid (CDCA). The highest DSSC device efficiency of 4.78 \% (Jsc of 8.77 mA/cm2 and Voc of 692 mV) has been achieved for SQA3. The IPCE profile of SQA dyes indicates the contribution of aggregated structures for the photocurrent generation. Further, co-sensitization of SQA3 dye with a complementary visible light active dye AK4 showed the enhanced device efficiency of 6.27 \% with panchromatic IPCE response. Dye rigidification, and controlled aggregation of dyes on TiO2 by means of cyclization of donor unit and introducing the alkyl groups in the dye structure synergistically improve the dye-sensitized solar cell (DSSC) device performance. Donor-Acceptor-Donor (D-A-D) based unsymmetrical squaraine dye SQA3 showed the DSSC device performance of 4.78 \%.image</p>
},
	keywords = {co-sensitization, dye-sensitized solar cell, effect of alkyl chain, molecular planarity, squaraine dye},
	issn = {2367-0932},
	doi = {10.1002/cptc.202300160},
	author = {Jadhav, Avinash P. and Singh, Ambarish Kumar and Maibam, Ashakiran and Krishnamurty, Sailaja and Krishnamoorthy, Kothandam and Nithyanandhan, Jayaraj}
}
@article {49326,
	title = {Far-red active unsymmetrical squaraine dyes containing N-arylated indoline donors for dye sensitized solar cells},
	journal = {Photochemistry and Photobiology},
	volume = {100},
	year = {2024},
	month = {JUL},
	pages = {1116-1126},
	type = {Article},
	abstract = {<p>
	Squaraine dyes possess sharp far-red active transition with high extinction coefficient and form aggregates on TiO2 surface. Aggregation of dyes on TiO2 has been considered as a detrimental factor for DSSC device performance, which can be controlled by appending alkyl groups to the dye structures. Hence by integrating alkylated (alkyl groups with both in-plane and out-of-plane) aryl group with indoline moiety to make it compatible with other electrolytes and for controlling the dye-aggregation, a series of squaraine acceptor-based dyes SQA4-6 have been designed and synthesized. SQA4-6 dyes showed absorption between 642 and 653 nm (lambda max), photophysical and electrochemical studies indicated that the HOMO energy levels of this sets of dyes are well aligned with the potentials of I-/I3-\$\$ {\textbackslashmathrm{I}}_3\&lt;\^\&gt;{-} \$\$ and [Co(bpy)3]2+/3+ redox shuttles for better dye regeneration process. DSSC device efficiency of 3\% has been achieved for SQA5 dye with iodolyte (I-/I3-\$\$ {\textbackslashmathrm{I}}_3\&lt;\^\&gt;{-} \$\$) electrolyte in the presence of 0.3 mM of chenodeoxycholic acid (CDCA). The IPCE profile of DSSC device fabricated with SQA4-6 dyes indicated the contribution of aggregated structures for the photocurrent generation. Dye-sensitized solar cell (DSSC) device efficiency of 3\% (Jsc 5.72 mA cm-2, Voc 662 mV and ff 79\%) has been achieved for an unsymmetrical squaraine dye, SQA5 with iodolyte electrolyte and the incident photon to current efficiency (IPCE) profile indicates the contribution of aggregated structures for the photocurrent generation.*image</p>
},
	keywords = {aggregation of dye, arylation on N-atom of indoline donor, dye-sensitized solar cell, squaraine dye},
	issn = {0031-8655},
	doi = {10.1111/php.13907},
	author = {Jadhav, Avinash P. and Singh, Ambarish Kumar and Pandya, Rinu and Vanka, Kumar and Krishnamoorthy, Kothandam and Jayaraj, Nithyanandhan}
}
