Y6 (BTP-4F) non-fullerene acceptor molecule for OPVs
Featured in Advance Science, Ossila Y6 solution processed thin-film transistors gained electron mobilities up to 2.4 cm2 V−1 s−1
Y6 is a popular non-fullerene acceptor (NFA) molecule. The discovery of ITIC and the subsequent boom in the use of NFAs in organic photovoltaic solar cells (OPVs) has led to rapid improvements in device power conversion efficiencies (PCEs). The development of new NFA molecules like Y6 has continued this exciting trend. Using Y6, considerable jumps in solar cell performance have been achieved.
Also known BTP-4F, Y6 is a highly conjugated electron deficient organic semiconductor with an A-DAD-A structure. The Y6 molecule is composed of a fused thienothienopyrrolo-thienothienoindole (TTP-TTI) core base and 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (2FIC) end units. These 2FIC end units are believed to promote intermolecular interactions and enhance optical absorption; the absorption spectrum of Y6 has a maximum at around 810 nm and extends to 1100 nm. This means that Y6 and its polymer blends have the potential to absorb light across the entire visible and near infra-red spectrum.
The benzothiadiazole core of Y6 allows for the creation of solar cells using the polymer PBDB-T-2F (PM6) as an electron donor. Impressive power conversion efficiencies of up to 15.7% have been demonstrated in optimised single-junction solar cells with both conventional and inverted architectures using Y6 and PM6.
|Thickness (nm)||VOC (V)||JSC (mA cm-2)||FF (%)||PCE (%)|
Y6 (BTP-4F) from Ossila was used in the high-impact paper (IF 29.37), Triplet-Charge Annihilation in a Small Molecule Donor: Acceptor Blend as a Major Loss Mechanism in Organic Photovoltaics, J. Marin-Beloqui et al., Adv. Energy Mater., 2100539 (2021); DOI: 10.1002/aenm.202100539. Y6 Organic Thin-Film Transistors with Electron Mobilities of 2.4 cm2 V−1 s−1 via Microstructural Tuning, E. Gutierrez-Fernandez et al., Adv. Sci., 9 (1), 2104977 (2022); DOI: 10.1002/advs.202104977.
Characterisation (1H NMR)
Y6 vs Y7 for OPVs
The success of the electron-deficient-core-based fused ring design of Y6 has led to the development of other non-fullerene acceptors for solar cells based on the same principle. One such molecule is the chlorinated form of BTP-4F, known as Y7 or BTP-4Cl. Using polymer donor PM6, devices created using BTP-4Cl have achieved a record PCE of 16.5%. This compares to 15.7% with Y6.
The absorption of Y7 is 20 nm redshifted compared to Y6 and its LUMO energy level is 100 meV lower.
Y7, NFA Molecule BTP-4Cl
- Chlorinated Version of Y6
- High Purity
- Low Price
Available From £190
Literature and Reviews
- Single-Junction Organic Solar Cell with over 15% Efficiency Using Fused-Ring Acceptor with Electron-Deficient Core, J. Yuan et al., Joule (2019); doi: 10.1016/j.joule.2019.01.004.
- Fluorination vs. chlorination: a case study on high performance organic photovoltaic materials, Y. Zhang et al., Sci. China. Chem., 61 (10), 1328-1337 (2018); doi:10.1007/s11426-018-9260-2.
- Achieving over 16% efficiency for single-junction organic solar cells, B. Fan et al., Sci. China Chem., 62, 6 746-752 (2019); doi: 10.1007/s11426-019-9457-5.
- 16.67% Rigid and 14.06% Flexible Organic Solar Cells Enabled by Ternary Heterojunction Strategy, Yan T et al., Adv Mater., 31(39):e1902210 (2019); doi: 10.1002/adma.201902210.
|Purity||>98% (1H NMR)|
|Molecular Weight||1451.93 g/mol|
|HOMO / LUMO||HOMO = -5.65 eV, LUMO = -4.10 eV |
|Synonyms||TTPTTI-4F, BTPTT-4F, BTP-4F, Y6F, BTP-4F-8|
|Classification / Family||NFAs, n-type non-fullerene electron acceptors, organic semiconducting materials, low band-gap small molecule, small molecular acceptor, organic photovoltaics, polymer solar cells, NF-PSCs|
MSDS DocumentationY6 (BTP-4F) MSDS Sheet
* Available with a lead time of 4-5 weeks
To the best of our knowledge the information provided here is accurate. However, Ossila assume no liability for the accuracy of this page. The values provided are typical at the time of manufacture and may vary over time and from batch to batch. All products are for laboratory and research and development use only, and may not be used for any other purpose including health care, pharmaceuticals, cosmetics, food or commercial applications.