Horizontal-, Vertical-, and Cross-Conjugated Small Molecules: Conjugated Pathway-Performance Correlations along Operation Mechanisms in Ternary Non-Fullerene Organic Solar Cells.
Sang Myeon LeeTanya KumariByongkyu LeeYongjoon ChoJungho LeeJiyeon OhMingyu JeongSungwoo JungChang Duk YangPublished in: Small (Weinheim an der Bergstrasse, Germany) (2020)
A family of the SM-axis series based on benzo[1,2-b:4,5-b']dithiophene and 3-ethylrhodanine (RD) units with structurally different π-conjugation systems are synthesized as a means to understand the structure-property relationship of conjugated pathways in ternary non-fullerene organic solar cells (NF-OSCs) as a third component. The optical and electrochemical properties of the SM-axis are highly sensitive both to the functionalized direction and to the number of RD groups. Enhanced power conversion efficiencies (PCEs) of over 11% in ternary devices are obtained by incorporating optimal SM-X and SM-Y contents from PBDB-T:ITIC binary NF-OSCs, while a slightly lower PCE is observed with the addition of SM-XY. The results of in-depth studies using various characterization techniques demonstrate that working mechanisms of SM-axis-based ternary NF-OSCs are distinctly different from one another: an energy-transfer mechanism with an alloy-like model for SM-X, a charge transfer with the same model for SM-Y, and an energy transfer without such a structure for SM-XY. As extension of the scope, a SM-X-based ternary NF-OSC in the PM6:IT4F system also shows a greatly enhanced PCE of over 13%. The findings provide insights into the effects of conjugated pathways of organic semiconductors on mechanisms of ternary NF-OSCs, advancing the understanding for synthetic chemists, materials engineers, and device physicists.
Keyphrases
- solar cells
- signaling pathway
- energy transfer
- lps induced
- oxidative stress
- pi k akt
- nuclear factor
- quantum dots
- photodynamic therapy
- reduced graphene oxide
- gold nanoparticles
- immune response
- inflammatory response
- high resolution
- air pollution
- toll like receptor
- optical coherence tomography
- visible light
- mass spectrometry
- label free