Three-dimensional D-π-A organic sensitizer with coplanar triphenylamine moiety for dye-sensitized solar cells

Photoisomerization of dicyanorhodanine-functionalized thiophenes

“…Early on, RCN was introduced to small molecule dye-sensitized solar cell (DSSC) materials, [6][7][8][9] including relatively high performers such as indoline-based D-A-p-A systems which have demonstrated power conversion efficiencies (PCEs) as high as 8.53% when using 2,1,3-benzothiadiazole as an internal acceptor. 10 More recently, DSSC small molecules relying on a triarylamine donor and RCN acceptor were developed [11][12][13] and have generated PCEs up to 8.98% for an optimized device using a Zn 2+ porphyrin co-sensitizer. 14 As interest in bulk-heterojunction (BHJ) devices increased, a plethora of small molecule (SM) donor materials relying on RCN appeared.…”

“…The acceptor group is introduced onto the terminus of thiophene oligomers via a Knoevenagel condensation reaction between 2-(1,1-dicyanomethylene)rhodanine and the corresponding pconjugated carboxaldehyde, typically in the last step of the synthetic sequence. 2,11,13,40 The condensation results in the formation of an olenic C]C double bond which has the potential for both Z and E stereochemistry ( Fig. 2).…”

“…While the olen stereochemistry of alkylmethylidene and arylmethylidene rhodanine (C]S) derivatives had been discussed previously, [75][76][77] and the thermodynamically stable Z isomer for aryl-and tetrathiafulvalene-based RCN structures has been conrmed by DFT, 1 this stereochemical feature has not been addressed for RCN-functionalized oligothiophenes and is generally ignored in the organic materials literature. To wit, some reports depict RCNfunctionalized oligothiophenes as the E isomer, 5,13,16,78 while others depict the Z conguration. 1,2,22,40 Given that even small structural changes in p-conjugated molecules can have concomitant effects on the efficiency of a photovoltaic device, [79][80][81][82][83] and thin lm packing/morphology of dye molecules is of critical importance to device efficiency, [84][85][86] ignoring this stereochemical feature may not be justied.…”

Development of Ruthenium Complex Based Sensitizers, Organic Based Sensitizers, and Co-sensitization System for Dye-sensitized Solar Cells

“…The unique orientation of the sensitizer could effectively prevent electron recombination and thus reached a VOC of 0.7 V, which was comparable to that of N719. More recently, a new 3D triphenylamine electron donor group was developed for an organic sensitizer (dye 37) to resist the charge recombination and dark current in a DSSC [41]. The novel 3D sensitizer had a 21.1% higher efficiency than the conventional triphenylamine donor.…”

Optoelectronic Properties of Triphenylamine Based Dyes for Solar Cell Applications. A DFT Study

“…24 Consequently, TPA are considered as ideal donor units in organic dyes, because are able to exhibit a good electron donating and high hole-transporting capability. 24,25 New dyes based on TPA as electron donor group have been studied from experimental, [26][27][28][29][30] and theoretical, 16,27,[31][32][33][34] point of views. Hence, a lot of effort has been dedicated to understand the relationship between the molecular structure of these dyes based on TPA, CA and different π-spacers, in order to analyze their charge-transporting properties.…”