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Product Code M2411A1-250mg
Price £270 ex. VAT

A frequent electron rich 2,2′-dimethylbenzidine derivative

A hole transport and injection materials for OLEDs and OPVs

α-NPD (CAS number 495416-60-9), namely N,N′-Bis(naphthalen-1-yl)-N,N′-bis(phenyl)-2,2′-dimethylbenzidine, is a bis(triarylamine) that is joined by a 2,2'-dimethylbiphenyl unit. The only difference to NPB (N,N′-Bis(naphthalen-1-yl)-N,N′-bis(phenyl)benzidine) is that α-NPD has two extra methyl groups on the biphenyl bridging unit.

Bearing two triarylamine units, α-NPD is electron rich and known as a typical hole transporting material for organic electronics (OLEDs, OPVs). It is believed that the introduction of methyl groups in meta position on the central biphenyl unit of α-NPD is to create the distortion of the molecular geometry and consequently a decrease of the electronic conjugation as well as an increase of the band gap.

It is worth noting that α-NPD has also been identified as N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)benzidine in a lot of literatures. Please check the chemical structure, CAS (chemical abstract service) number and chemical name before you place the order with us.

General Information

CAS Number 495416-60-9
Full Name N,N'-Bis(naphthalen-1-yl)-N,N'-bis(phenyl)-2,2'-dimethylbenzidine
Synonyms 2,2′-Dimethyl-N,N′-di-[(1-naphthyl)-N,N′-diphenyl]-1,1′-biphenyl-4,4′-diamine, α-NPD
Chemical Formula C46H36N2
Molecular Weight 616.79 g/mol
HOMO/LUMO HOMO = ~5.4 eV, LUMO = ~2.4 eV
Classification / Family Triarylamine derivatives, Hole transport materials, Sublimed materials

Product Details

Purity Sublimed >99.0% (HPLC)
Melting Point >310 °C (0.5% weight loss)
Appearance White to off-white powder/crystals

Chemical Structure

α-NPD, 495416-60-9, N,N'-Bis(naphthalen-1-yl)-N,N'-bis(phenyl)-2,2'-dimethylbenzidine chemical structure
Chemical Structure of N,N'-Bis(naphthalen-1-yl)-N,N'-bis(phenyl)-2,2'-dimethylbenzidine (α-NPD), CAS 495416-60-9

Device Structures

Device structure ITO/HAT-CN (5 nm)/TAPC (30 nm)/mCP (15 nm)/1.0 wt% TXOPhCz4:o,o'-NPh2 (20 nm)/TmPyPB (50 nm)/LiF (0.9 nm)/Al (90 nm) [1]
Colour white light emitting device White (0.38, 0.40)
Max. Current Efficiency 30.2 cd/A
Max. EQE 12.5%
Max. Power Efficiency 27.1 lm W-1

MSDS Documentation


Literature and Reviews

  1. Highly efficient white light-emitting diodes with a bi-component emitting layer based on blue and yellow thermally activated delayed fluorescence emitters, J. Mater. Chem. C, 6, 2951 (2018); DOI: 10.1039/c8tc00594j.
  2. Resolving the Spatial Variation and Correlation of Hyperfine Spin Properties in Organic Light-Emitting Diodes, W. Pappas et al., Adv. Mater., 34 (11), 2104186 (2022); DOI: 10.1002/adma.202104186.
  3. Nonradiative Recombination via Charge-Transfer-Exciton to Polaron Energy Transfer Limits Photocurrent in Organic Solar Cells, S. Khan et al., Adv. Energy, Mater., 12 (19), 2200551 (2022); DOI: 10.1002/aenm.202200551.
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