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Product Code M2185A1-500mg
Price £260 ex. VAT

NPB-DPA, HIL material in OLED devices

Sublimed and unsublimed grades are available for NPB-DPA

NPB-DPA, full name N,N'-Bis[4-(diphenylamino)phenyl]-N,N'-di(1-naphthyl)benzidine, is a derivative of triarylamines. It has a skeleton of two joined triarylamines with two diphenylamine as pending units. It is electron-rich and commonly used as a hole-injection layer (HIL) material in OLED devices.

NPB is normally used as a hole-transporting layer (HTL) material. In comparison, NPB-DPA is inserted between an ITO anode and a HTL to effectively modify the cathode surface and facilitate the collection of the holes to the electrode.

Like NPB-DPA, NPB's sister compound NPNPB is also commonly used as the buffer layer between a HTL and an anode to lower the barrier of the hole injections.

General Information

CAS number 910058-11-6
Full name N,N'-Bis[4-(diphenylamino)phenyl]-N,N'-di(1-naphthyl)benzidine, N,N’-Bis[4-(diphenylamino)phenyl]-N,N’-di-1-naphthalenyl-[1,1′-biphenyl]-4,4′-diamine
Chemical formula C68H50N4
Molecular weight 923.18 g/mol
Absorption* λmax 355 nm in DCM
Fluorescence λmax 515 nm in DCM
HOMO/LUMO HOMO = 5.2 eV, LUMO = 1.9 eV [1]
Classification / Family Triarylamines, Hole-transport layer (HTL) materials, Hole-injection layer (HIL) materials, Electron-blocking layer materials, OLED materials, Sublimed materials, Organic electronics.

* Measurable with an optical spectrometer, see our spectrometer application notes.

Product Details

Purity Sublimed* >99% (HPLC); Unsublimed >98%
Melting point n/a
Appearance Off-white crystal/powder

* Sublimation is a technique used to obtain ultra pure-grade chemicals, see sublimed materials.

Chemical Structure

npb-dpa chemical structure
Chemical structure of NPB-DPA

Device Structure(s)

Device structure ITO/NPB-DPA (60 nm)/TBB (30 nm)/NA-MSBAF*:DSA-Ph (30 nm, 5%)/LG201* (20 nm)/LiF/Al [1]
Colour Sky-blue blue light emitting device
Max. Luminance 11,080 cd/m2
Max. Current Efficiency 7.67 cd/A
Max. EQE 5.15%
Device structure ITO/NPB-DPA (60 nm)/TBB (30 nm)/NA-SBAF*:DSA-Ph (30 nm, 5%)/LG201* (20 nm)/LiF/Al [1]
Colour Sky-blue blue light emitting device
Max. Luminance 13,020 cd/m2
Max. Current Efficiency 7.73 cd/A
Max. EQE 4.93%
Device structure ITO/NPB-DPA (60 nm)/TBB (30 nm)/NSBTF*:DSA-Ph (30 nm, 5%)/LG201* (20 nm)/LiF/Al [1]
Colour Sky-blue blue light emitting device
Max. Current Efficiency 7.91 cd/A
Max. EQE 4.76%

*For chemical structure information, please refer to the cited references


Grade (Purity) Order Code Quantity Price
Sublimed (>99%) M2185A1 500 mg £260
Sublimed (>99%) M2185A1 1 g £400
Sublimed (>99%) M2185A1 5 g £1300
Unsublimed* (>98%) M2185B1 5 g £520
Unsublimed* (>98%) M2185B1 100 g £5000
*For unsublimed grade orders, the lead time is 2-3 weeks. For orders larger than 100 g, please contact us.

MSDS Documentation


Literature and Reviews

  1. New spirobenzoanthracene derivatives with naphthylanthracene core: Synthesis and application in sky-blue fluorescent host materials, M. Kim et al., Dyes and Pigments 105, 202-207 (2014); doi: 10.1016/j.dyepig.2014.02.005.
  2. New spiro[benzotetraphene-fluorene] Derivatives: Synthesis and Application in Sky-Blue Fluorescent Host Materials, J. Cha et al., J. Fluoresc., 24, 1215–1224 (2014); DOI: 10.1007/s10895-014-1403-2.
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