Insulating Polymers as additives into Bulk-Heterojunction Organic Solar Cells: The Effect of Miscibility

Chemphyschem. 2021 Nov 17. doi: 10.1002/cphc.202100725. Online ahead of print.ABSTRACTThe adding of insulating polymers into conjugated polymers is an efficient strategy to tailor their mechanical properties for flexible organic electronics. In this work, we selected two insulating polymers as additives into high-performance photoactive layers to study the mechanical and photovoltaic properties in organic solar cells (OSCs). The insulating polymers were found to reduce the electron mobilities in the photoactive layers, and hence the power conversion efficiencies were significantly decreased. More importantly, we found that the insulating polymers exhibited negative effect on the mechanical properties of the photoactive layers, with reduced young's modules and low crack onset strain. Further studies revealed that the insulating polymers had poor miscibility with the photoactive layers, providing large domains in blend thin films, which act as the force accumulation point during the tensile test. The studies indicate that rational selection of insulating polymers, especially enhancing the non-covalent interaction with the photoactive layers, will be critically important for the stretch OSCs.PMID:34791762 | DOI:10.1002/cphc.202100725

Source: Chemphyschem - November 18, 2021 Category: Chemistry Authors: Chunhui Liu Chengyi Xiao Weiwei Li Chengcheng Xie Qinglian Zhu Qiaomei Chen Wei Ma Source Type: research