Br-2PACz, or (2-(3,6-dibromo-9H-carbazol-9-yl)ethyl)phosphonic acid (CAS 2762888-11-7), is a self-assembled monolayer (SAM) material for hole transport and hole extraction layers in p-i-n perovskite solar cells and non-fullerene acceptor (NFA) polymer solar cells. A dibrominated derivative of 2PACz, it combines an electron-rich carbazole terminal group with an ethyl phosphonic acid anchoring group. It is supplied as an off-white powder or crystals with a purity above 99% by 1H NMR.
Applying Br-2PACz to indium-tin-oxide raises its work function from 4.73 eV to 5.82 eV. In Cs0.25FA0.75Sn0.5Pb0.5I3 perovskite cells, devices using it as the hole transport layer reached a record 19.51% efficiency, against 16.33% with PEDOT:PSS. These devices kept 80% of their starting efficiency after 230 h of continuous illumination, even following 4224 h of storage under N2.
Br-2PACz offers an alternative to PEDOT:PSS and can be deposited from dilute solution, typically 1 mM, in solvents such as ethanol, methanol, THF, IPA or DMF, followed by spin coating and annealing at 100 °C.
- Hole transport layer in p-i-n perovskite solar cells, including Sn/Pb mixed perovskites.
- Hole extraction interlayer in organic and NFA-polymer solar cells.
- Hole-selective contact in silicon-perovskite tandem devices.
- Work function modification of ITO electrodes.
- Hole-injecting interlayer in perovskite-organic blend light-emitting diodes.
| Brand | Ossila |
|---|---|
| CAS number | 2762888-11-7 |
| Molecular formula | C14H12Br2NO3P |
| Purity | > 99% (1H NMR) |
| Category | — |
| Pack sizes | 500 mg, 1 g |
| Physical form | Off-white powder/crystals |
| Storage | — |
- Product code: M2426A1
- Molecular Weight: 433.03 g/mol
- Absorption: λ max 458 nm (ITO)
- HOMO/LUMO: HOMO = 6.01 eV, LUMO = 2.64 eV
- Synonym: (2-(3,6-Dibromo-9H-carbazol-9-yl)ethyl)phosphonic acid
- Typical Solvents: Ethanol, methanol, THF, IPA, DMF
- Typical Concentration: 1 mM (0.433 mg/ml) or 1.0 mg/ml
An MSDS is available for Br-2PACz; consult it before handling the material.
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