TY - JOUR
T1 - Thiocyanate-Free Ruthenium(II) Sensitizers for Dye-Sensitized Solar Cells Based on the Cobalt Redox Couple
AU - Wu, Kuan-Lin
AU - Clifford, John N.
AU - Wang, Sheng-Wei
AU - Aswani, Yella
AU - Palomares, Emilio
AU - Lobello, Maria Grazia
AU - Mosconi, Edoardo
AU - De Angelis, Filippo
AU - Ku, Wan-Ping
AU - Chi, Yun
AU - Nazeeruddin, Mohammad K.
AU - Grätzel, Michael
PY - 2014/10
Y1 - 2014/10
N2 - Two thiocyanate-free ruthenium(II) sensitizers, TFRS-41 and TFRS-42, with distinctive dialkoxyphenyl thienyl substituents were successfully prepared and tested for potential applications in making dye-sensitized solar cells (DSCs). Subsequent device fabrication was conducted by using a [Co(bpy)3]2+/3+-based (bpy=2,2'-bipyridine) electrolyte, for which the best performance data, namely, JSC=13.11 mAcm-2, VOC=862 mV, fill factor=0.771, and η=8.71%, were recorded for the sensitizer TFRS-42 with a 2,6-dialkoxyphenyl substituent under AM 1.5G irradiation. The markedly higher Voc value was confirmed by the longer electron lifetime revealed in transient photovoltage (TPV) measurements versus the TFRS-1 sensitizer. In addition, DFT calculation and detailed first-principles computational analysis were conducted to provide a rationale for the observed trends in their photovoltaic performances and electron lifetimes, with reference to different performances exhibited by three thiocyanate-free sensitizers, TFRS-1, TFRS-41 and TFRS-42, versus Z907 reference. Through the proper control of peripheral substituents, the thiocyanate-free ruthenium(II)-based DSC sensitizers can positively influence the performances of DSCs, with better light-harvesting capability and suppressed charge recombination, for DSC cells fabricated by using a [Co(bpy)3]2+/3+-based electrolyte.
AB - Two thiocyanate-free ruthenium(II) sensitizers, TFRS-41 and TFRS-42, with distinctive dialkoxyphenyl thienyl substituents were successfully prepared and tested for potential applications in making dye-sensitized solar cells (DSCs). Subsequent device fabrication was conducted by using a [Co(bpy)3]2+/3+-based (bpy=2,2'-bipyridine) electrolyte, for which the best performance data, namely, JSC=13.11 mAcm-2, VOC=862 mV, fill factor=0.771, and η=8.71%, were recorded for the sensitizer TFRS-42 with a 2,6-dialkoxyphenyl substituent under AM 1.5G irradiation. The markedly higher Voc value was confirmed by the longer electron lifetime revealed in transient photovoltage (TPV) measurements versus the TFRS-1 sensitizer. In addition, DFT calculation and detailed first-principles computational analysis were conducted to provide a rationale for the observed trends in their photovoltaic performances and electron lifetimes, with reference to different performances exhibited by three thiocyanate-free sensitizers, TFRS-1, TFRS-41 and TFRS-42, versus Z907 reference. Through the proper control of peripheral substituents, the thiocyanate-free ruthenium(II)-based DSC sensitizers can positively influence the performances of DSCs, with better light-harvesting capability and suppressed charge recombination, for DSC cells fabricated by using a [Co(bpy)3]2+/3+-based electrolyte.
KW - cobalt
KW - dyes/pigments
KW - ruthenium
KW - sensitizers
KW - solar cells
UR - http://www.scopus.com/inward/record.url?scp=84908406565&partnerID=8YFLogxK
UR - https://www.scopus.com/record/pubmetrics.uri?eid=2-s2.0-84908406565&origin=recordpage
U2 - 10.1002/cssc.201402030
DO - 10.1002/cssc.201402030
M3 - RGC 21 - Publication in refereed journal
C2 - 25146378
SN - 1864-5631
VL - 7
SP - 2930
EP - 2938
JO - ChemSusChem
JF - ChemSusChem
IS - 10
ER -
