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Product Code M2257A1
Price $600.00 ex. VAT

BTR-Cl, highly crystalline small molecular donor

High purity and available online for fast, secure dispatch

Like its BTR derivative, BTR-Cl has a backbone consisting of a benzodithiophene (BDT) unit in conjugation with two terthiophenes and two rhodanine periphera end groups forming a coplanar structure showing nematic liquid crystal behaviour.

BTR-Cl is a highly crystalline small molecular donor with even stronger intermolecular interaction, low-lying molecular energy levels, strong intermolecular interaction, and a strong tendency for edge-on orientation.

A record-high power conversion efficiency (PCE) of 13.6% for ASM OSCs was achieved using BTR-Cl as electron donor and Y6 as electron acceptor [1]. Later on, 14.7% efficiency of the same donor acceptor BTR-Cl:Y6 system was obtained with a FF of 74.7%, and JSC of 23.66 mA cm-2 at the concentration of 18 mg/ml BTR-Cl:Y6 solution [2]. Further improvement leading to a record PCE of 15.34% was gained when 5 wt% of PC71BM was added in the active layer [3]

Device structure 1: ITO/PEDOT:PSS/BTR-Cl:Y6 (1.6:1)/Phen-NaDPO/Ag

Thickness (nm) VOC (V) JSC (mA cm-2) FF (%) PCE (%)
110 0.86 24.0 64.6 13.61

Device structure 2: ITO/PEDOT:PSS/BTR-Cl:Y6 (1.6:1)/Phen-NaDPO/Ag

Thickness (nm) VOC (V) JSC (mA cm-2) FF (%) PCE (%)
110 0.83 23.66 74.7 14.70

Total concentration of the active layer is 18 mg/ml

Device structure 3: ITO/PEDOT:PSS/BTR-Cl:Y6:5 wt% PC71BM (1.8:1:0.1)/Phen-NaDPO/Ag

Thickness (nm) VOC (V) JSC (mA cm-2) FF (%) PCE (%)
110 0.838 23.75 77.11 15.34

General Information

Full name 5,5'- [[4,8-bis[5-(2-ethylhexyl)-4-chloro-2-thienyl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl]bis[(3',3''-dihexyl[2,2':5',2''-terthiophene]-5'',5-diyl)methylidyne ]]bis[3-hexyl-2-thioxo-4-thiazolidinone]
Purity 98% (1H NMR)
Synonyms BTR-Cl
Chemical formula C102H126Cl2N2O2S14
Molecular weight 1931.97 g/mol
CAS number 2410661-17-3
HOMO / LUMO HOMO = -5.46 eV LUMO = -3.70 eV [1]
Melting point (DSC) 226°C, 195°C (Tg)
Absorption λmax 580 nm, 624 nm in film
Color/form Dark purple powder/crystals
Solubility/processing solvents Chloroform, chlorobenzene
Classification / Family Benzodithiophene (BDT) derivatives, Heterocyclic five-membered ring, Organic semiconducting materials, Organic Photovoltaics, Small molecule donor, SM-OPVs, Liquid crystal

Chemical Structure

BTR-Cl, OPV small molecule donor
Chemical structure of BTR-Cl, OPV small molecule donor, CAS# 2410661-17-3.

MSDS Documentation



Batch Quantity Price
M2257A1 100 mg £480
M2257A1 250 mg £950
M2257A1 500 mg £1800
M2257A1 1 g £3200
M2257A1 5 - 10 g* Please enquire
*For order quantities of 5 - 10 grams, the lead time is 4-6 weeks.

Literature and Reviews

  1. All-Small-Molecule Organic Solar Cells with an Ordered Liquid Crystalline Donor, H. Chen et al., Joule 3, 3034–3047 (2019); DOI: 10.1016/j.joule.2019.09.009.
  2. Delicate Morphology Control Triggers 14.7% Efficiency All-Small-Molecule Organic Solar Cells, H Tang et al., Adv. Energy Mater., 2001076 (2020); DOI: 10.1002/aenm.202001076.
  3. 15.34% Efficiency All-Small-Molecule Organic Solar Cells with Improved Fill Factor Enabled by a Fullerene Additive, D. Hu et al., Energy Environ. Sci., 13, 2134-2141 (2020); DOI: 10.1039/D0EE00714E.
  4. A molecular nematic liquid crystalline material for high-performance organic photovoltaics, K. Sun et al., Nat. Commun., 6:6013 (2014); DOI: 10.1038/ncomms7013.

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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