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Product Code M2426A1-500mg
Price £170 ex. VAT

Self-assembled Monolayer for Stable Solar Cells

Br-2PACz, Carbazole-based phosphonic acid hole transport or extraction layer for NFA-polymer solar cells and p-i-n perovskite solar cells, CAS No. 2762888-11-7

Br-2PACz, also known as (2-(3,6-dibromo-9H-carbazol-9-yl)ethyl)phosphonic acid, is a diborminated derivative of its parent compound 2PACz. It has an electron-rich carbazole unit and a binding ethyl phosphonic acid functional group.

Carbazole-based self-assembled monolayers have been widely used in Pb-based perovskite solar cells and silicon-perovskite tandem devices. The work function of indium-tin-oxide increases dramatically from 4.73 eV to 5.82 eV upon functionalization with Br-2PACz.

A record efficiency of 19.51% was achieved in Cs0.25FA0.75Sn0.5Pb0.5I3 perovskite solar cells when Br-2PACz was engaged as a hole transport layer material, while an efficiency of 16.33% was recorded by using PEDOT:PSS. The Br-2PACz-based devices also gave better device stability and longer shelf-life, maintaining 80% of their initial efficiency under continuous illumination for 230 h, even after the fabricated device was being stored in a N2 atmosphere for 4224 h [1].

Serving as hole selective contact for organic solar cells and perovskite solar cells, Br-2PACz is an alternative to PEDOT:PSS with superior performance with the convenience of solution deposition at low concentration, i.e. 1 mM.

Solution Processing Procedure

Typical processing solvents: ethanol, methanol, THF, IPA, DMF
Typical concentration: 1 mM (0.433 mg/ml) or 1.0 mg/ml (1 mg Br-2PACz is dissolved in 1 ml ethanol)

Typical processing procedure: 100 uL of Br-2PACz solution is deposited onto the centre of the substrate surface and spin-coated for 30 s at the speed of 3000 rpm . After annealing for 10 min at 100 ℃. EtOH solution (200 µl) was dynamically spin coated on ITO/SAM at 3000 rpm for 30 s to remove the aggregates, and the substrates were annealed at 100 °C for 1 min. 

General Information

CAS Number 2762888-11-7
Chemical Formula C14H12Br2NO3P
Molecular Weight 433.03 g/mol
Absorption* λmax 458 nm (ITO)
Fluorescence λem (n.a.)
HOMO/LUMO HOMO = 6.01 eV, LUMO = 2.64 eV
Synonyms (2-(3,6-Dibromo-9H-carbazol-9-yl)ethyl)phosphonic acid
Classification or Family Carbazole derivatives, Self-assembly Monolayers, Hole transport layer, Hole extraction layer, p-i-n Perovskite solar cells, Organic photovoltaics

Product Details

Purity > 99% (1H NMR)
Melting Point n.a.
Appearance Off-white powder/crystals

Chemical Structure

br-2pacz- 2762888-11-7 - (2-(3,6-Dibromo-9H-carbazol-9-yl)ethyl)phosphonic acid chemical structure
Br-2PACz - (2-(3,6-Dibromo-9H-carbazol-9-yl)ethyl)phosphonic acid chemical structure, 2762888-11-7

MSDS Documentation

br-2pacz- 2762888-11-7 - (2-(3,6-dibromo-9H-carbazol-9-yl)ethyl)phosphonic acidBr-2PACz MSDS Sheet

Literature and Reviews

  1. 18.4 % Organic Solar Cells Using a High Ionization Energy Self-Assembled Monolayer as Hole-Extraction Interlayer, Y. Lin et al., ChemSusChem, 14 (17), 3569-3578 (2021); DOi: 10.1002/cssc.202100707.
  2. A carbazole-based self-assembled monolayer as the hole transport layer for efficient and stable Cs0.25FA0.75Sn0.5Pb0.5I3 solar cells, M. Pitaro et al., J. Mater. Chem. A, 11, 11755-11766 (2023); DOI: 10.1039/D3TA01276J.
  3. 18.9% Efficient Organic Solar Cells Based on n-Doped Bulk-Heterojunction and Halogen-Substituted Self-Assembled Monolayers as Hole Extracting Interlayers, Y. Lin et al., Adv. Energy Mater., 12 (45), 2202503 (2022); DOI: 10.1002/aenm.202202503.
  4. 18.73% efficient and stable inverted organic photovoltaics featuring a hybrid hole-extraction layer, Y. Lin et al., Mater. Horiz., 10, 1292-1300 (2023); DOI: 10.1039/D2MH01575G.
  5. Tuning the Surface Energy of Hole Transport Layers Based on Carbazole Self-Assembled Monolayers for Highly Efficient Sn/Pb Perovskite Solar Cells, M. Pitaro et al., Adv. Funct. Mater., 2306571 (2023); DOI: 10.1002/adfm.202306571.
  6. High-Efficiency Perovskite–Organic Blend Light-Emitting Diodes Featuring Self-Assembled Monolayers as Hole-Injecting Interlayers, M. Gedda et l., Adv. Energy Mater., 13 (33), 2201396 (2023); DOI: 10.1002/aenm.202201396.

Licensed by Helmholtz-Zentrum Berlin für Materialien und Energie GmbH in Germany and Kaunas University of Technology in Lithuania.

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