Side-chains Engineering of Conjugated Polymers toward Additive-free Non-fullerene Organic Solar Cells
- PDF / 356,161 Bytes
- 8 Pages / 595.35 x 842 pts (A4) Page_size
- 17 Downloads / 196 Views
POLYMER SCIENCE
ARTICLE
https://doi.org/10.1007/s10118-020-2490-y Chinese J. Polym. Sci.
Side-chains Engineering of Conjugated Polymers toward Additive-free Non-fullerene Organic Solar Cells Feng Liua,b, Dan Wanga,b, Jun-Yu Lib, Cheng-Yi Xiaob, Yong-Gang Wua, Wei-Wei Lib*, and Guang-Sheng Fua* a College of Physics Science & Technology, Hebei University, Baoding 071002, China b Beijing
Advanced Innovation Center for Soft Matter Science and Engineering & State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China
Electronic Supplementary Information Abstract Side-chain engineering plays a significant role in the design of conjugated materials. In this work, a series of conjugated polymers PBDB-T-R with functionalized groups at the end of side units were developed as electron donor for organic solar cells (OSCs). The donor polymers PBDB-T-I and PBDB-T-OAc with iodine and acetate end groups exhibited similar absorption and energy levels, but showed much improved PCEs in OSCs compared to the polymer PBDB-T-H without substitutions at the end groups. Additionally, we found that PBDB-T-I and PBDB-T-OAc based cells exhibited optimized performance when using chloroform as solution-processed solvent without any additives. These results indicate that these conjugated polymers can act as self-additive to fabricate photoactive layers via solution process in OSCs. Keywords Organic solar cells; Non-fullerene; End group; Additive; Crystallinity Citation: Liu, F.; Wang, D.; Li, J. Y.; Xiao, C. Y.; Wu, Y. G.; Li, W. W.; Fu, G. S. Side-chains engineering of conjugated polymers toward additive-free nonfullerene organic solar cells. Chinese J. Polym. Sci. https://doi.org/10.1007/s10118-020-2490-y
INTRODUCTION Non-fullerene organic solar cells (NFOSCs) have attracted much attention due to their advantages of high performance, lowcost, easy processing and thus potential large-area application.[1−10] Recently, Zou et al. developed a ladder-type acceptor Y6 with strong absorption in the near-infrared region (NIR).[11] NFOSCs based on Y6 as electron acceptor and wide-bandgap benzodithiophenedione (BDT)-based donor polymers (such as PM6 and PM7) provided excellent PCEs (15%−18%).[12−18] It is important to put continuous efforts into material design and device engineering in order to further enhance the PCEs of NFOSCs. Besides the conjugated backbone engineering, side-chain engineering plays a significant role in the material design. Side chains of conjugated polymers can influence the solubility, aggregation and crystalline properties, and charge transport properties.[19−22] Many works have focused on modifying side chains, such as via introducing fluorine and chlorine atoms,[23,24] alkyloxy and alkylthio units,[25] thienyl and phenyl side units,[26] etc. In addition, the device engineering, for instance, through using high boiling point additive during solution-processing for photoactive layers, is
* Corresponding authors, E-mail: [email protected] (W.W.L.)
Data Loading...
