Revealing Morphology Evolution in Highly Efficient Bulk Heterojunction and Pseudo-Planar Heterojunction Solar Cells by Additives TreatmentShow others and affiliations
2021 (English)In: Advanced Energy Materials, ISSN 1614-6832, E-ISSN 1614-6840, Vol. 11, no 7, article id 2003390Article in journal (Refereed) Published
Abstract [en]
Additives treatment is as a very effective strategy to optimize bulk heterojunction (BHJ) morphology. However, the inherent working mechanism of this strategy still lacks systematical investigations in non-fullerene-acceptors-based organic solar cells (OSCs). Herein, a series of BHJ and pseudo-planar heterojunction (PPHJ) OSCs using PM6 and IT-4F as the electron donor/acceptor pair, are developed to unveil the promoting effect of solvent additive 1, 8-diiodooctane (DIO) on active layer morphologies and device performance. The study clearly demonstrates that DIO can increase the crystallinity of IT-4F significantly, while it has less impact on PM6. It is notable that a new efficiency-determining crystalline balanced factor (CCLpolymer/CCLacceptor) is put forward, indicating that the more balanced CCLpolymer/CCLacceptor results in more balanced charge mobility and much better short-circuit current densities (J(sc)) and fill factors (FF) of OSCs. The PPHJ blend film of PM6/IT-4F(DIO) exhibits enhanced crystallinity with more balanced CCL and favorable hierarchical distribution morphology, contributing to a champion efficiency of 13.70% with a record J(sc) of 20.98 mA cm(-2) and a remarkable FF of 75.9%. This work not only reveals the underlying mechanism of DIO caused morphology evolution, but also achieves highly efficient PPHJ OSCs with superior thermal stability by elaborately controlling the morphology of PPHJ film.
Place, publisher, year, edition, pages
WILEY-V C H VERLAG GMBH , 2021. Vol. 11, no 7, article id 2003390
Keywords [en]
bulk heterojunctions; crystal coherence length; morphology regulation; organic solar cells; pseudo-planar heterojunctions
National Category
Other Chemistry Topics
Identifiers
URN: urn:nbn:se:liu:diva-173096DOI: 10.1002/aenm.202003390ISI: 000607547700001OAI: oai:DiVA.org:liu-173096DiVA, id: diva2:1524267
Note
Funding Agencies|National Natural Science Foundation of China (NSFC)National Natural Science Foundation of China (NSFC) [51973110, 21734009]
2021-02-012021-02-012022-03-17