التفاصيل البيبلوغرافية
| العنوان: |
In situ monitoring drying process to disclose the correlation between the molecular weights of a polymer acceptor with a flexible spacer and the performance of all-polymer solar cells |
| المؤلفون: |
Xiang, Jiale, Englund, Sven, Genene, Zewdneh, Wen, Guanzhao, Liu, Yanfeng, Yao, Nannan, 1992, Zhang, Rui, Qin, Leiqiang, 1987, Wang, Lei, 1989, Wang, Ergang, Zhang, Wei, Zhang, Fengling, 1960 |
| المصدر: |
Journal of Materials Chemistry C. 12(33):13029-13039 |
| الوصف: |
Molecular weight (M-n) and conjugation of polymers can profoundly influence the performance of all-polymer solar cells (all-PSCs) via nanostructures of bulk heterojunctions (BHJs). To study the correlation between M-n and the performance of all-PSCs based on an acceptor with a flexible conjugation-break spacer (FCBS), three batches of acceptors, named PYTS, were synthesized with different number-average M-n from 9, 13 to 19 kDa. Blends with a polymer donor PBDB-T, the all-PSCs based on PYTS with M-n of 9 kDa and 19 kDa, exhibit power conversion efficiencies (PCEs) of 5.99% and 9.43%, respectively, primarily due to the increased short-circuit current density (J(sc)) from 13.02 to 18.73 mA cm(-2). To disclose the impact of M-n on device performance, dynamics of mixed PBDB-T:PYTS solutions to solid BHJs is studied by monitoring the drying process with home-made in situ multifunctional spectroscopy, which demonstrates that PYTS with M-n of 19 kDa has a longer drying time than the PYTS with M-n of 9 kDa. Prolonged drying of the BHJs with higher M-n PYTS facilitates more tightly packed structures with higher crystallinity. A systematic investigation on the nanostructures of BHJs, charge generation, transport and recombination is carried out with grazing-incidence wide-angle X-ray scattering (GIWAXS), transient absorption spectroscopy (TAS) and characterization of all-PSCs. The results indicate that increased crystallinity in the BHJs benefits exciton dissociation, electron transport, prolonged carrier lifetimes, and decreased non-geminate recombination rate constants in the corresponding devices. Combining the in situ study of drying and the investigation on films and devices provides us a comprehensive understanding of the interplay between M-n, the drying process, the nanostructures of BHJs and device performance. This work not only emphasizes the essential role of M-n in governing the device performance, but also exhibits recorded film formation through the in situ spectroscopy, enabling us to manipulate the nanostructure of BHJs by optimizing M-n of polymers and processing parameters. |
| وصف الملف: |
print |
| URL الوصول: |
https://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-206343 |
| قاعدة البيانات: |
SwePub |