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Product Code M2337A1-250mg
Price $475 ex. VAT

POSTF, high quality and high purity bipolar host material

Phosphorescent host for highly efficient blue, green and red phosphorescence devices

POSTF, namely 2'-(Diphenylphosphoryl)-10-phenyl-10H-spiro[acridine-9,9'-fluorene], has an orthogonal molecular structure with an electron donating spiro[acridine-9,9'-fluorene] core and one electron withdrawing diphenylphosphine oxide attachment to the fluorene unit at 2-poistion.

Bipolar POSTF can be used as a single or together with PO-T2T as an exciplex phosphorescent host for highly efficient blue, green and red phosphorescence devices. Using POSTF as the host, large-size white light-emitting panel (15 cm × 15 cm) with max power efficiency of 75.9 lm W-1 can be achieved [1].

General Information

CAS number 1647050-25-6
Full name 2'-(Diphenylphosphoryl)-10-phenyl-10H-spiro[acridine-9,9'-fluorene]
Chemical formula C43H30NOP
Molecular weight 607.68 g/mol
Absorption λmax 280 nm, 325 nm (in DCM)
Phosphorescene λmax 430 nm (in DCM)
HOMO/LUMO HOMO = 5.57 eV, LUMO = 2.12 eV [1]
Synonyms Diphenyl(10-phenyl-10H-spiro[acridine-9,9'-fluoren]-2'-yl)phosphine oxide
Classification / Family Spiro[acridine-9,9'-fluorene] derivatives, Light-emitting diodes, Bipolar host, TADF host materials, Sublimed materials.

Product Details

Purity Sublimed >99.0% (HPLC)
Melting point Tg = 160 ℃, Td (Temperature at 5% weight loss) = 356 ℃.
Appearance White powder/crystals

*Sublimation is a technique used to obtain ultra pure-grade chemicals. For more details about sublimation, please refer to the Sublimed Materials.

Chemical Structure

POSTF chemical structure
Chemical structure of 2'-(Diphenylphosphoryl)-10-phenyl-10H-spiro[acridine-9,9'-fluorene] (POSTF), CAS# 1647050-25-6.

Device Structure(s)

Device structure ITO/HAT-CN (10 nm)/TAPC (45 nm)/POSTF: FIrpic (15 vol%, 20 nm)/TmPyPB (40 nm)/Liq (2 nm)/Al [1]
Colour blue light emitting device Blue
Max. Power Efficiency 50.5 lm W-1
Max. EQE 26.8%
Device structure ITO/HAT-CN/TAPC/POSTF/POSTF:POT2T:15 mol% FIrpic/POSTF:PO-T2T:Ir(MDQ)2(acac)/PO-T2T/Liq/Al [2]
Colour white light emitting device White
Max. Power Efficiency 60.7 lm W-1
Max. EQE 24.7%
Device structure ITO/HAT-CN/TAPC/ POSTF/POSTF:PO-T2T: 15% FIrpic (CRS)/PO-T2T/Liq/Al [2]
Colour blue light emitting device Blue
Max. Power Efficiency 34.7 lm W-1
Max. EQE 20.1%
Device structure ITO/HAT-CN/TAPC/ POSTF/POSTF:PO-T2T: 15% FIrpic (CRS)/PO-T2T/Liq/Al [2]
Colour blue light emitting device Blue
Max. Power Efficiency 57.4 lm W-1
Max. EQE 19.3%
Device structure ITO/HAT-CN/TAPC/ POSTF/POSTF:PO-T2T: 15% Ir(MDQ)2(acac) (CRS)/PO-T2T/Liq/Al [2]
Colour red light emitting device Red
Max. Power Efficiency 46.0 lm W-1
Max. EQE 27.6%

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


Grade Order Code Quantity Price
Sublimed (>99.0% purity) M2337A1 250 mg £380
Sublimed (>99.0% purity) M2337A1 500 mg £660
Sublimed (>99.0% purity) M2337A1 1 g £1150

MSDS Documentation


Literature and Reviews

  1. Orthogonal Molecular Structure for Better Host Material in Blue Phosphorescence and Larger OLED White Lighting, L. Ding et al., Adv. Funct. Mater., 25 (4); 645-650 (2015); DOI: 10.1002/adfm.201403402.
  2. High-Quality White Organic Light-Emitting Diodes Composed of Binary Emitters with Color Rendering Index Exceeding 80 by Utilizing Color Remedy Strategy, X. Tang et al., Adv. Funct. Mater., 29 (11); 1807541 (2019); DOI: 10.1002/adfm.201807541.
  3. Theoretical Investigations of the Spiro-Annulated Triphenylamine/ N-Phenylcarbazole-Based Ambipolar Host Materials for OLEDs, D. Zhang, et al., ChemistrySelect, 2 (22), 6604-6611 (2017); DOI: 10.1002/slct.201701424.
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