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CAS Number 1644381-95-2

Non-Fullerene Acceptors

Product Code M2242A1-100mg
Price $388 ex. VAT

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FBR molecule, NFA which reduces the tendency of crystallization

Used to achieve one of the highest open voltages for polymer organic solar cells

FBR, having a similar AA-D-AA type structure to IDFBR, contains electron-donating alkylated fluorene as the core, flanked by electron withdrawing benzothiadiazole (BT) and 3-ethylrhodanine units on the periphery terminals.

FBR reduces the tendency of crystallization and helps to prevent the formation of large crystalline domains in the BHJ donor/acceptor blend composition leading to better device performance efficiency and longer life-times.

Comparing to PC71BM, FBR has a relatively high lowest unoccupied molecular orbital (LUMO) which in theory should give a higher open voltage (Voc). This is indeed the case for polymer organic solar cells with PffBT4T-2DT as the polymer donor and FBR as the electron acceptor, yielding a device performance efficiency over 7.8% with an open voltage of 1.12 eV. This is one of the highest achieved open voltages for polymer organic solar cells.

Device structure: ITO/ZnO/PffBT4T-2DT:FBR/MoOx/Ag [1]

Thickness (nm) VOC (V) JSC (mA cm-2) FF (%) PCE (%)
120 1.12 11.5 61 7.8

Chemical Structure

Chemical structure of FBR, CAS 1644381-95-2

Literature and Reviews

  1. Reduced voltage losses yield 10% efficient fullerene free organic solar cells with >1 V open circuit voltages, D. Baran et al., Energy Environ. Sci., 9, 3783--3793 (2016); DOI: 10.1039/c6ee02598f.
  2. A Rhodanine Flanked Nonfullerene Acceptor for Solution-Processed Organic Photovoltaics, S. Holliday et al., J. Am. Chem. Soc., 137, 2, 898–904 (2015); doi: 10.1021/ja5110602.
  3. Critical review of the molecular design progress in non-fullerene electron acceptors towards commercially viable organic solar cells, A. Wadsworth et al., Chem. Soc. Rev., 48, 1596 (2019); DOI: 10.1039/c7cs00892a.
  4. Influence of Blend Morphology and Energetics on Charge Separation and Recombination Dynamics in Organic Solar Cells Incorporating a Nonfullerene Acceptor, H. Cha et al., Adv. Funct. Mater., 1704389 (2017); doi: 10.1002/adfm.201704389.

General Information

CAS Number 1644381-95-2
Chemical Formula C53H56N6O2S6
Purity >98% (1H NMR)
Full Name 5,5′-[(9,9-Dioctyl-9H-fluorene-2,7-diyl)bis(2,1,3-benzothiadiazole-7,4-diylmethylidyne)]bis[3-ethyl-2-thioxo-4-thiazolidinone]
Molecular Weight 1001.44 g/mol
Absorption* λmax 510 nm (Film)
HOMO / LUMO HOMO = -5.83 eV, LUMO = -3.75 eV [1]
Solubility Chloroform, chlorobenzene
Form Red powder/crystals
Synonyms (5Z,5'Z)-5,5'-((7,7'-(9,9-dioctyl-9H-fluorene-2,7-diyl)bis(benzo[c][1,2,5]thiadiazole-7,4-diyl))bis(methanylylidene))bis(3-ethyl-2-thioxothiazolidin-4-one)
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.

*Measurable with the Ossila Optical Spectrometer, see more on Spectrometers and Spectroscopy Accessories.

MSDS Documentation



Batch Quantity Price
M2242A1 100 mg £310
M2242A1 250 mg £620
M2242A1 500 mg £1100
M2242A1 1 g £2000

To the best of our knowledge the information provided here is accurate. The values provided are typical at the time of manufacture and may vary over time and from batch to batch. Products may have minor cosmetic differences (e.g. to the branding) compared to the photos on our website. All products are for laboratory and research and development use only.

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