02578nas a2200181   4500008004100000245017900041210006900220260000800289300001600297490000600313520181900319100002502138700002902163700002802192700002402220700002702244856012502271       2016                        eng d00aEffect of out-of-plane alkyl group's position in dye-sensitized solar cell efficiency: a structure-property relationship utilizing indoline-based unsymmetrical squaraine dyes0 aEffect of outofplane alkyl groups position in dyesensitized sola  cDEC  a35353-353670 v83 a<p>Squaraine dyes are promising chromophores to harvest visible and near-infrared (NIR) photons. A series of indoline-based unsymmetrical squaraine (SQ) dyes that contain alkyl chains at sp(3) C- and N- atoms of indoline moieties with a carboxylic acid anchoring group were synthesized. The optical and electrochemical properties of the SQ dyes in solution were nearly identical as there was no change in the D-A-D SQ framework; however, remarkable changes with respect to the power conversion efficiencies (PCE) were observed depending upon the position of alkyl groups in the dye. Introduction of alkyl groups to the indoline unit that was away from anchoring unit were helped in more dye loading with controlled organization of dyes on surface, increased charge transfer resistance, long electron lifetime, and hence higher PCE than that of the corresponding isomer in which the alkyl groups funtionalized indoline unit contains the carboxylic acid anchoring group. Careful analysis of incident photon-to current conversion efficiency (IPCE) profiles indicated the presence of aggregated structure on the TiO2 surface that contributes to the charge injection in the presence of a coadsorbent. A dye-sensitized solar cell (DSSC) device made out of SQ5 was achieved an efficiency of 9.0%, with an open-circuit potential (V-oc) of 660 mV and short-circuit current density (J(sc)) of 19.82 mA/cm 2, under simulated AM 1.5G illumination (100 mW/cm(2)). The IPCE profile of SQ5 shows an onset near to 750 nm with a good quantum efficiency (&gt;80%) in the range of 550-700 nm, indicating the importance of self-organization of dyes on the TiO2 surface for an efficient charge injection. This present investigation revealed the importance of position of alkyl groups in the squaraine-based dyes for the better PCE.</p>1 aAlagumalai, Ananthan1 aFairoos, Munavvar, M. K.1 aVellimalai, Punitharasu1 aSil, Manik, Chandra1 aNithyanandhan, Jayaraj  uhttps://library.ncl.res.in/content/effect-out-plane-alkyl-groups-position-dye-sensitized-solar-cell-efficiency-structure