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Product Code M2242A1
Price $350.00 ex. VAT

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 an optical spectrometer, see our spectrometer application notes.

MSDS Documentation



Batch Quantity Price
M2242A1 100 mg £280
M2242A1 250 mg £560
M2242A1 500 mg £1000
M2242A1 1 g £1800

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.

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