TY - JOUR
T1 - Pyranylidene/trifluoromethylbenzoic acid-based chromophores for dye-sensitized solar cells
AU - Royo, Raquel
AU - Domínguez-Celorrio, Amelia
AU - Franco, Santiago
AU - Andreu, Raquel
AU - Orduna, Jesús
N1 - Funding Information:
Financial support from Ministerio de Ciencia e Innovación ( PID2019-104307 GB-I00/AEI/10.13039/501100011033 ) and Gobierno de Aragón-FEDER-Fondo Social Europeo ( E47_20R ) is gratefully acknowledged. R. Royo acknowledges for the financial support of Gobierno de Aragón: Fellowship program 2018–2022 period co-financed with the Operational Program FSE Aragón 2014-202. We thank Dr. B. Villacampa (University of Zaragoza, Spain) for helpful discussions. Authors would like to acknowledge the use of Servicio General de Apoyo a la Investigación-SAI, Universidad de Zaragoza.
Funding Information:
The photovoltaic properties of the sensitizers were evaluated under standard AM 1.5 G illumination (100 mW cm−2) using a solar simulator (See Supporting Information). The solar cells were fabricated following a protocol that we have already described in previous papers. In this series, the optimized concentration was defined as 0.1 mM for the sensitizer and 0.3 mM for the antiaggregant additive chenodeoxycholic acid in anhydrous CH2Cl2. (Mixtures EtOH/CH2Cl2 (1:1) and increased concentrations of antiaggregant were also tested, although there is not improvement in the results). The liquid electrolyte was based on the redox I−/I3− system (1-butyl-3-methylimidazolium iodide (0.53 M), LiI (0.10 M), I2 (0.050 M) and tert-butylpyridine (0.52 M) in anhydrous acetonitrile). The photoanodes were prepared using the screen-printing technique with a commercial TiO2 paste (Dyesol® 18NR-AO) and an effective area of 0.25 cm2. The thickness of active layer was optimized to 13 μm and the dipping time was set to 8 h.Financial support from Ministerio de Ciencia e Innovación (PID2019-104307 GB-I00/AEI/10.13039/501100011033) and Gobierno de Aragón-FEDER-Fondo Social Europeo (E47_20R) is gratefully acknowledged. R. Royo acknowledges for the financial support of Gobierno de Aragón: Fellowship program 2018–2022 period co-financed with the Operational Program FSE Aragón 2014-202. We thank Dr. B. Villacampa (University of Zaragoza, Spain) for helpful discussions. Authors would like to acknowledge the use of Servicio General de Apoyo a la Investigación-SAI, Universidad de Zaragoza.
Publisher Copyright:
© 2022 The Authors
PY - 2022/10
Y1 - 2022/10
N2 - The synthesis and photovoltaic study of five dyes based on 4H-pyranylidene moiety as donor moiety is reported. A thiophene unit conjugated with/without an ethynyl bond acts as the π-relay and benzoic acid as the anchor group with/without a trifluoromethyl group. Their electrochemical and optical properties are analyzed by using a joint experimental and theoretical approach. The presence of the trifluoromethyl group leads to an enhancement of the molar extinction coefficient, being slightly when a hexyl chain is introduced in the thiophene ring, but does not modify the oxidation potential. For the preparation of derived solar cells an antiaggregant is essential in all cases. The photovoltaic performance is sensitive to the structural modification of the dye: the CF3 group and the hexyl chain of the thiophene spacer were shown to improve the efficiency. The lack of a triple bond in the π-spacer involves a lower photovoltaic efficiency, and the trifluoromethyl group leads to a lower dye-load, but a decrease of the recombination processes. These results are in accordance with the electrochemistry impedance spectroscopy studies carried out. Moreover, the organic dyes have been also tested with a fluorescent lamp (indoor conditions), leading to an increase of the efficiency, reaching a 36% for the best dye.
AB - The synthesis and photovoltaic study of five dyes based on 4H-pyranylidene moiety as donor moiety is reported. A thiophene unit conjugated with/without an ethynyl bond acts as the π-relay and benzoic acid as the anchor group with/without a trifluoromethyl group. Their electrochemical and optical properties are analyzed by using a joint experimental and theoretical approach. The presence of the trifluoromethyl group leads to an enhancement of the molar extinction coefficient, being slightly when a hexyl chain is introduced in the thiophene ring, but does not modify the oxidation potential. For the preparation of derived solar cells an antiaggregant is essential in all cases. The photovoltaic performance is sensitive to the structural modification of the dye: the CF3 group and the hexyl chain of the thiophene spacer were shown to improve the efficiency. The lack of a triple bond in the π-spacer involves a lower photovoltaic efficiency, and the trifluoromethyl group leads to a lower dye-load, but a decrease of the recombination processes. These results are in accordance with the electrochemistry impedance spectroscopy studies carried out. Moreover, the organic dyes have been also tested with a fluorescent lamp (indoor conditions), leading to an increase of the efficiency, reaching a 36% for the best dye.
KW - D-π-A dyes
KW - 4H-pyranylidene
KW - DSSC
KW - Trifluoromethyl group
UR - http://www.scopus.com/inward/record.url?scp=85136639678&partnerID=8YFLogxK
U2 - 10.1016/j.dyepig.2022.110566
DO - 10.1016/j.dyepig.2022.110566
M3 - Article
AN - SCOPUS:85136639678
SN - 0143-7208
VL - 206
JO - Dyes and Pigments
JF - Dyes and Pigments
M1 - 110566
ER -
