TY - JOUR
T1 - Flexible Organic Photovoltaics with Star-Shaped Nonfullerene Acceptors End Capped with Indene Malononitrile and Barbiturate Derivatives
AU - Al-Anesi, Basheer
AU - Revoju, Srikanth
AU - Hiltunen, Arto
AU - Suhonen, Riikka
AU - Kraft, Thomas M.
AU - Liu, Maning
AU - Zhang, Haichang
AU - Deng, Zhifeng
AU - Fedele, Chiara
AU - Berdin, Alex
AU - Lamminen, Noora
AU - Grandhi, G. Krishnamurthy
AU - Ylikunnari, Mari
AU - Vivo, Paola
PY - 2022/8
Y1 - 2022/8
N2 - The design and synthesis of three star-shaped nonfullerene (NFA) acceptors, TPA-2T-INCN, TPA-2T-BAB, and TPA-T-INCN, based on a triphenylamine (TPA) core and linked through π-conjugated thiophene (T) spacers to different terminal units (3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile, INCN, and 1,3-dimethylbarbituric acid, BAB), are reported. These materials are blended with the widely used poly(3-hexylthiophene-2,5-diyl) (P3HT) donor polymer and tested in flexible organic photovoltaics (OPVs). The NFAs capped with the strong electron-withdrawing INCN unit perform best in OPVs. Both P3HT:TPA-T-INCN and P3HT:TPA-2T-INCN blends also show the highest photoluminescence quenching efficiency (95.8% and 92.6%, respectively). Surprisingly, when reducing the number of T spacers from 2 to 1, the solubility of the NFAs in o-dichlorobenzene increases, leading to easier processing during the OPV fabrication and better surface morphology. This explains the best performance of TPA-T-INCN-based blends in OPVs, with a champion power conversion efficiency of 1.13%.
AB - The design and synthesis of three star-shaped nonfullerene (NFA) acceptors, TPA-2T-INCN, TPA-2T-BAB, and TPA-T-INCN, based on a triphenylamine (TPA) core and linked through π-conjugated thiophene (T) spacers to different terminal units (3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile, INCN, and 1,3-dimethylbarbituric acid, BAB), are reported. These materials are blended with the widely used poly(3-hexylthiophene-2,5-diyl) (P3HT) donor polymer and tested in flexible organic photovoltaics (OPVs). The NFAs capped with the strong electron-withdrawing INCN unit perform best in OPVs. Both P3HT:TPA-T-INCN and P3HT:TPA-2T-INCN blends also show the highest photoluminescence quenching efficiency (95.8% and 92.6%, respectively). Surprisingly, when reducing the number of T spacers from 2 to 1, the solubility of the NFAs in o-dichlorobenzene increases, leading to easier processing during the OPV fabrication and better surface morphology. This explains the best performance of TPA-T-INCN-based blends in OPVs, with a champion power conversion efficiency of 1.13%.
KW - barbiturate
KW - flexible photovoltaics
KW - indene malononitrile
KW - nonfullerene acceptors
KW - organic photovoltaics
KW - star-shaped acceptors
U2 - 10.1002/ente.202200264
DO - 10.1002/ente.202200264
M3 - Article
AN - SCOPUS:85132346622
SN - 2194-4288
VL - 10
JO - Energy Technology
JF - Energy Technology
IS - 8
M1 - 2200264
ER -
