Y7, also known as BTP-4Cl, is the chlorinated version of Y6 (BTP-4F). It has an absorption range that extends to the near infrared (NIR) and has demonstrated a power conversion efficiency (PCE) up to 15.7% with PBDB-T-2F (PM6) as the polymer donor.
Like Y6, Y7 is a highly conjugated organic semiconductor and is composed of a fused thienothienopyrrolo-thienothienoindole (TTP-TTI) core base and 2-(5,6-dichloro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (2ClIC) end units. Y7 has an A-DAD-A structure and is therefore electron deficient and hence suitable for use as a n-type non-fullerene electron acceptor (NFA) in OPV devices.
Compared to Y6, the chlorinated acceptor Y7 shows a redshift of about 20 nm in optical absorption and about 100 meV downshift in the LUMO level. Device film containing Y7 has a higher electroluminescence quantum efficiency (EQE = 3.47 × 10-4) than that of Y6 (1.40 × 10-4) with reduced non-radiative energy loss of ~ 24 meV. This reduced non-radiative energy loss yields a higher VOC of 0.867 V compared with that of the Y6 based device (0.834 V).
Record PCEs of 16.5% and 15.3% for OPV cells with 0.09 and 1 cm2 active areas were achieved when PBDB-T-2F (PM6) was used as the polymer donor and Y7 as the acceptor with the following device structure.
Device structure: ITO/ZnO/PM6:Y7/MoO3/Al.
|Thickness (nm)||VOC (V)||JSC (mA cm-2)||FF (%)||PCE (%)|
|100 ± 4||0.867||25.4||75.0||16.5 (16.1 ± 0.2)|
Characterisation (1H NMR)
|Purity||>99% (1H NMR)|
|Form||Solid powder: Dark blue to black|
|Synonyms||BTP-4Cl, Y6Cl, TTPTTI-4Cl|
|CAS number||Not available|
|Molecular weight||1517.75 g/mol|
|HOMO / LUMO||HOMO = -5.65 eV, LUMO = -3.63 eV |
|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.|
BTP-4Cl MSDS Sheet
Literature and Reviews
- Over 16% efficiency organic photovoltaic cells enabled by a chlorinated acceptor with increased open-circuit voltages, Y Cui et al., Nat. Commun., 10, 2515 (2019) doi: 10.1038/s41467-019-10351-5
- 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.
- 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.
To the best of our knowledge the technical information provided here is accurate. However, Ossila assume no liability for the accuracy of this information. The values provided here are typical at the time of manufacture and may vary over time and from batch to batch.