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Product Code M2426A1-500mg
Price $213 ex. VAT

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Self-assembled Monolayer for Stable Solar Cells

Carbazole-based phosphonic acid hole transport or extraction layer for NFA-polymer solar cells and p-i-n perovskite solar cells


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].

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.

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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