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Product Code M401-5g
Price £300 ex. VAT

TPD, HTL material in organic electronic devices

Used as a blue-violet light emitting material or host material on the PhOLEDs

Overview | Specifications | MSDS | Literature and Reviews

N,N′-Bis(3-methylphenyl)-N,N′-diphenylbenzidine, CAS number 65181-78-4, commonly abbreviated as TPD, is widely used as hole transport materials in organic electronic devices.

TPD is also used as a blue-violet light emitting material or host material on the phosphorescence organic light emitting diodes for its wide energy band being about 3.2 eV with highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) being 5.5 eV and 2.3 eV respectively [1, 2].

TPD from Ossila was used in the high-impact paper (IF 14.92)

TPD from Ossila was used in the high-impact paper (IF 14.92), Complete polarization of electronic spins in OLEDs, T. Scharff et al., Nat. Commun., 12, 2071 (2021); DOI: 10.1038/s41467-021-22191-3.

General Information

CAS Number 65181-78-4
Chemical Formula C38H32N2
Molecular Weight 516.67 g/mol
Absorption* λmax 352 nm in THF
Fluorescence λem 398 nm in THF
HOMO/LUMO HOMO = 5.5 eV, LUMO = 2.3 eV
Synonyms TPD, N,N′-Bis(3-methylphenyl)-N,N′-diphenylbenzidine, N,N'-Diphenyl-N,N'-di(m-tolyl)benzidine, 4,4'-Bis[N-phenyl-N-(m-tolyl)amino]biphenyl
Classification / Family Triphenylamine derivatives, Hole-injection materials, Hole transporting materials, Phosphorescent host materials, Light-emitting diodes, Organic electronics, Sublimed materials

*Measurable with the Ossila Optical Spectrometer, see our spectrometer and accessories.

Product Details

Purity Sublimed* >99%
Melting Point 175 – 177 °C (lit.)
Colour White powder/crystals

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

Chemical Structure

N,N′-Bis(3-methylphenyl)-N,N′-diphenylbenzidine tpd chemical structure
Chemical Structure of N,N′-Bis(3-methylphenyl)-N,N′-diphenylbenzidine (TPD)

Device Structure(s)

Device Structure ITO/m-MTDATA/TPD/F-TBB*/Alq3/MgAg [1]
Colour Blue blue light emitting device
Max EQE 1.4%
Maximum luminance 3960 cd m-2 at 15.0 V
Device Structure ITO/75 wt% TPD:25 wt% PC (50nm) /TCTA (10nm)/6 % PtL30Cl*:94 % [TCTA: TCP] [1:1] (30 nm)/TAZ (30 nm)/LiF/Al [3]
Colour White white light emitting device
EQE@500 cd/m2 11.3%
Current Efficiency@500 cd/m2 23.5 cd/A
Bias 9.3 V
Device Structure ITO/m-MTDATA*:F4-TCNQ (100 nm)/TPD (5 nm)/Alq3 (20 nm)/BPhen (10 nm)/Bphen:Li (30 nm)/LiF (1 nm)/Al (100 nm) [4]
Colour Green green light emitting device
Max. Luminance 10,000 cd/m2 at 5.2 V
Max. Current Efficiency 5.27 cd/A
Device Structure ITO/CuPc(10 nm)/TPD(50 nm)/Bepp2 (40 nm)/LiF(1.5 nm)/Al(200 nm) [5]
Colour Blue blue light emitting device
Max. Luminance 4,000 cd/m2
Max. Power Efficiency 0.55 lm W−1
Device Structure ITO/TPD (50 nm)/BePP2 (5 nm)/TPD (4 nm)/BePP2:rubrene (5 nm)/TPD (4 nm)/Alq (10 nm)/Al [6]
Colour White white light emitting device
Max. Luminance 20,000 cd/m2
Max. Power Efficiency 1.11 lm W−1
Device Structure ITO/CuPc (18 nm)/TPD (50 nm)/Alq3 (60 nm)/BCP (10 nm)/LiF (1 nm)/Al (100 nm) [8]
Colour Green green light emitting device
Max. Luminance 5,993 cd/m2
Max. Current Efficiency 3.82 cd/A
Max. Power Efficiency 2.61 lm W-1
Device Structure ITO/PEDOT:PSS/PVK:OXD-7:TPD:(Et-Cvz-PhQ)2Ir(pic)*/OXD-7 (20 nm)/Ba (3 nm)/Al (100 nm) [9]
Colour Red red light emitting device
Max. Current Efficiency 17.5 cd/A
Max. EQE 10.6%
Max. Power Efficiency 6.42 lm W−1
Device Structure ITO/TPD (50 nm)/Zn(BTZ)2 (50 nm)/MgIn (200 nm) [10]
Colour Greenish-White white light emitting device
Max. Luminance 10,190 cd/m2
Max. Power Efficiency 0.89 lm W−1

*For chemical structure informations please refer to the cited references.


hplc trace of tpd
HPLC trace of N,N′-Bis(3-methylphenyl)-N,N′-diphenylbenzidine (TPD).

MSDS Documentation


Literature and Reviews

  1. Development of high-performance blue-violet-emitting organic electroluminescent devices, K. Okumoto et al., Appl. Phys. Lett. 79(9), 1231–1233 (2001).
  2. Efficiency and Aging Comparison Between N,N′-Bis (3-methylphenyl)-N,N′-diphenylbenzidine (TPD) and N,N′-Di-[(1-naphthalenyl)-N,N′-diphenyl]-1,1′-biphenyl-4,4′-diamine (NPD) Based OLED Devices, M. Maglione et al., Macromol. Symp., 247, 311–317 (2007).
  3. Blue-shifting the monomer and excimer phosphorescence of tridentate cyclometallated platinum(II) complexes for optimal white-light OLEDs, L. Murphy et al., Chem. Commun., 48, 5817-5819 (2012), DOI: 10.1039/C2CC31330H.
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