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Product Code M2257A1-100mg
Price £520 ex. VAT

BTR-Cl, highly crystalline small molecular donor

High purity and available online for fast, secure dispatch

Like its BTR derivative, BTR-Cl (CAS number 2410661-17-3) 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, and a strong tendency for edge-on orientation.

Multi-functional molecule

Multi-functional molecule

Nematic liquid crystal behaviour

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Small molecule donor in OPVs

Small molecule donor in OPVs

Achieving PCE over 15%

Highly crystalline molecule

Highly crystalline molecule

Low-lying molecular energy levels.

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 £520
M2257A1 250 mg £1050
M2257A1 500 mg £2000
M2257A1 1 g £3500
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.
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