FREE shipping on qualifying orders when you spend or more. All prices ex. VAT. Enjoy hassle-free delivery, fulfilled by our EU subsidiary. Backed by our 50 State Delivery Guarantee. Regional distributors also available. Sorry, we are unable to accept orders from or ship to .

It looks like you are using an unsupported browser. You can still place orders by emailing us on info@ossila.com, but you may experience issues browsing our website. Please consider upgrading to a modern browser for better security and an improved browsing experience.


Product Code M2453A1-500mg
Price $260 ex. VAT

Small Self-Assembled Monolayer Molecule for High Efficiency Solar Cells

MeO-4PACz, Hole transport or extraction layer for NFA-polymer solar cells and p-i-n perovskite solar cells


MeO-4PACz (4-(3,6-Dimethoxy-9H-carbazol-9-yl)butyl)phosphonic acid, CAS No. 2922526-56-3) is a self-assemble monolayer (SAM) material. It bears 3,6-dimethoxy-9H-carbazole as the hydrophobic electron rich terminal, butyl chain as the spacer, and phosphonic acid as the anchor to the surface of the electrode. As an alternative to Me-4PACz, the introduction of the methoxy group is aimed to improve the wettability of the SAM on the surface of the electrode and mitigate the poor deposition reproducibility of the active perovskite layer.

The longer alkyl spacer allows small molecules such as (aminomethyl)phosphonic acid (AMP) to sink and anchor to the buried interface to fill the voids of the self-assembled monolayer. With the help of further sequential modification of perovskite active layer surface by 2-(3-fluorophenyl)ethylamine iodide (mF-PEAI) and piperazine diiodide (PDI), uniform surface potential can be achieved, and recombination losses at the interface are thus minimized. Inverted MA-free perovskite solar cells achieved power conversion efficiency (PCE) of 25.35% (certified: 24.87%) and maintained 92.8% of the initial efficiency after 1000 h of maximum power output tracking.

Serving as hole selective contact for organic solar cells and perovskite solar cells, MeO-4PACz 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: Anhydrous ethanol (methanol, IPA, IPA/DMF are also superior solvents)
Typical concentration: 1 mM (0.363 mg/mL) - 1.0 mg/ml
Typical processing procedure: 40 uL of MeO-4PACz solution (0.363 mg in 1 ml IPA) is deposited onto the centre of the substrate surface and spin-coated for 30 s at the speed of 5000 rpm then annealed for 10 min at 100 ℃. The substrate is further washed by IPA to remove residual self-assembly molecules (DOI: 10.1002/aenm.202304486)

General Information


CAS Number 2922526-56-3
Chemical Formula C18H22NO5P
Molecular Weight 363.34 g/mol
Absorption* λmax (n.a)
Fluorescence λem (n.a.)
HOMO/LUMO HOMO = 5.32 eV, LUMO = 2.05 eV
Synonyms (4-(3,6-Dimethoxy-9H-carbazol-9-yl)butyl)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 > 98% (HPLC)
Melting Point 197 °C
Appearance White powder


Chemical Structure


meo-4pacz - 2922526-56-3 - (4-(3,6-dimethoxy-9H-carbazol-9-yl)butyl)phosphonic acid chemical structure
MeO-4PACz - (4-(3,6-Dimethoxy-9H-carbazol-9-yl)butyl)phosphonic acid chemical structure, CAS 2922526-56-3

MSDS Documentation


meo-4pacz - 2922526-56-3 - (4-(3,6-dimethoxy-9H-carbazol-9-yl)butyl)phosphonic acidMeO-4PACz MSDS Sheet

Literature and Reviews


  1. Glycol Monomethyl Ether-Substituted Carbazolyl Hole-Transporting Material for Stable Inverted Perovskite Solar Cells with Efficiency of 25.52%, H. Zhou et al., Angew. Chem. Int. Ed., e202403068 (2024); DOI: 10.1002/anie.202403068.
  2. Co-deposition of hole-selective contact and absorber for improving the processability of perovskite solar cells, X. Zheng e tal., Nat. Energy, 8, pages 462–472 (2023); DOI: 10.1038/s41560-023-01227-6.
  3. All-Round Passivation Strategy Yield Flexible Perovskite/CuInGaSe2 Tandem Solar Cells with Efficiency Exceeding 26.5%, L. Tang et al., Adv. Mater., 2402480 (2024); DOI: 10.1002/adma.202402480.
  4. Infiltrated 2D/3D Heterojunction with Tunable Electric Field Landscape for Robust Inverted Perovskite Solar Cells with over 24% Efficiency, C. Tang et al., Small, 2306978 (2024); DOI: 10.1002/smll.202306978.
  5. Dual-Interface Modification for Inverted Methylammonium-Free Perovskite Solar Cells of 25.35% Efficiency with Balanced Crystallization, Y. Zheng et al., Adv. Energy Mater., 2304486 (2024); DOI: 10.1002/aenm.202304486.

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

Return to the top