POSTF 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

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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

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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

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

Device Structure(s)

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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
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
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
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
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
Max. Power Efficiency	46.0 lm W-1
Max. EQE	27.6%