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Product Code M2411A1-250mg
Price $338 ex. VAT

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A frequent electron rich 2,2′-dimethylbenzidine derivative

A hole transport and injection materials for OLEDs and OPVs


α-NPD, 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

α-NPDα-NPD MSDS Sheet

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.
  4. Electro-Optic Properties of High-Efficiency Organic Electronics with the Addition of An Interlayer, S. Lee et al., Appl. Sci., 13, 624 (2023); DOI: 10.3390/app13010624.
  5. White-light electroluminescence from a layer incorporating a single fully-organic spiro compound with phosphine oxide substituents, P Tourneur et al., J. Mater. Chem. C, 8, 14462-14468 (2020); DOI: 10.1039/d0tc03285a.
  6. Influence of exciton lifetime on charge carrier dynamics in an organic heterostructure, K. Agrawal et al., Appl. Phys. Lett., 102, 113304 (2013); DOI: 10.1063/1.4795523.

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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