TY - JOUR
T1 - Asymmetric selenophene-based non-fullerene acceptors for high-performance organic solar cells
AU - Li, Chao
AU - Xia, Tian
AU - Song, Jiali
AU - Fu, Huiting
AU - Ryu, Hwa Sook
AU - Weng, Kangkang
AU - Ye, Linglong
AU - Woo, Han Young
AU - Sun, Yanming
N1 - Funding Information:
This work was financially supported by the National Natural Science Foundation of China (NSFC) (No. 21674007, 21734001, and 51825301). HYW acknowledges the financial support from the National Research Foundation (NRF) of Korea (2012M3A6A7055540 and 2015M1A2A2057506).
Funding Information:
This work was nancially supported by the National Natural Science Foundation of China (NSFC) (No. 21674007, 21734001, and 51825301). HYW acknowledges the nancial support from the National Research Foundation (NRF) of Korea (2012M3A6A7055540 and 2015M1A2A2057506).
PY - 2019
Y1 - 2019
N2 - Compared to thiophene-based non-fullerene acceptors (NFAs), selenophene-based NFAs have received much less attention. And organic solar cells (OSCs) based on selenophene-containing NFAs typically exhibit relatively low power conversion efficiency (PCE < 12%) and fill factor (FF < 70%). In this contribution, we have designed and synthesized two asymmetric selenophene-based NFAs, named SePTT-2F and SePTTT-2F, which possess the same end-capping group but different selenophene-containing conjugated backbones. On comparing the two NFAs, SePTTT-2F with more extended conjugation in the backbone was found to have almost the same maximum absorption peak and optical bandgap in film as SePTT-2F but an up-shifted lowest unoccupied molecular orbital (LUMO) energy level and higher electron mobility. By pairing the NFAs with the polymer donor PBT1-C, the resultant blend film based on SePTTT-2F exhibited higher and more balanced charge mobilities and more efficient exciton dissociation and charge collection in comparison with the SePTT-2F-based blend film. As a result, OSCs based on SePTTT-2F delivered an impressively high PCE of 12.24% with an outstanding FF of 75.9%, much higher than those of the SePTT-2F-based OSCs. To the best of our knowledge, the PCE of 12.24% and FF of 75.9% are among the highest values reported in the literature so far for both the parameters amongst selenophene-containing NFA-based OSCs. Our results demonstrate that extending the conjugation in the selenophene-containing backbone is an effective strategy to design highly efficient selenophene-based NFAs.
AB - Compared to thiophene-based non-fullerene acceptors (NFAs), selenophene-based NFAs have received much less attention. And organic solar cells (OSCs) based on selenophene-containing NFAs typically exhibit relatively low power conversion efficiency (PCE < 12%) and fill factor (FF < 70%). In this contribution, we have designed and synthesized two asymmetric selenophene-based NFAs, named SePTT-2F and SePTTT-2F, which possess the same end-capping group but different selenophene-containing conjugated backbones. On comparing the two NFAs, SePTTT-2F with more extended conjugation in the backbone was found to have almost the same maximum absorption peak and optical bandgap in film as SePTT-2F but an up-shifted lowest unoccupied molecular orbital (LUMO) energy level and higher electron mobility. By pairing the NFAs with the polymer donor PBT1-C, the resultant blend film based on SePTTT-2F exhibited higher and more balanced charge mobilities and more efficient exciton dissociation and charge collection in comparison with the SePTT-2F-based blend film. As a result, OSCs based on SePTTT-2F delivered an impressively high PCE of 12.24% with an outstanding FF of 75.9%, much higher than those of the SePTT-2F-based OSCs. To the best of our knowledge, the PCE of 12.24% and FF of 75.9% are among the highest values reported in the literature so far for both the parameters amongst selenophene-containing NFA-based OSCs. Our results demonstrate that extending the conjugation in the selenophene-containing backbone is an effective strategy to design highly efficient selenophene-based NFAs.
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U2 - 10.1039/c8ta11197a
DO - 10.1039/c8ta11197a
M3 - Article
AN - SCOPUS:85060464064
VL - 7
SP - 1435
EP - 1441
JO - Journal of Materials Chemistry A
JF - Journal of Materials Chemistry A
SN - 2050-7488
IS - 4
ER -