CzBN

CAS Number 2170487-27-9

Dopant Materials, High Purity Sublimed Materials, Materials, Semiconducting Molecules, TADF Materials

Blue Dopant Material with Boron-based Triarylamines

High purity sublimed narrowband multi-resonance TADF emitter for highly efficient OLEDs

CzBN (CAS number 2170487-27-9), also known as Indolo[3,2,1-de]indolo[3',2',1':8,1][1,4]benzazaborino[2,3,4-kl]phenazaborine, is closely related to DABNA-1 in structure. The only difference being is that the two phenylamines on each side of the DABNA-1 structure are joined to form two side carbazolyl substructures. As a result, CzBN is conjugated with a triphenyl boron core and it is believed that the formed carbazolyl groups extend the p-conjugation and increase the intramolecular charge transfer localization area for a greater multiresonance effect.

CzBN can also be considered as a derivate of 1,3-bis(N-carbazolyl)benzene (mCP), one of the most widely used host materials in OLED devices.

Due to the conjugation, CzBN is relatively red shifted in absorption and emission when compared to DABNA-1. CzBN has an absorption band at around 470 nm and narrow emission band at 479 nm with FWHM of 30 nm in dilute dichloromethane solution and PLQYs of 87%.

A solution processed sky-blue multiresonance TADF OLED device, based on 5 wt.% CzBN in a CzAcSF host, exhibited a maximum current efficiency of 24.3 cd/A, a power efficiency of 15.9 lm/W, and an external quantum efficiency of 14.7%. This is a device efficiency improvement when compared to the vacuum-deposited OLEDs based on DABNA-1.

General Information

CAS Number	2170487-27-9
Chemical formula	C₃₀H₁₇BN₂
Molecular weight	416.28 g/mol
Absorption*	λ_max 470 nm (in DCM)
Fluorescence	λ_em 479 nm (in DCM)
HOMO/LUMO	HOMO = 5.62 eV, LUMO = 2.91 eV (ΔE_ST = 0.12 eV)
Synonyms	Indolo[3,2,1-de]indolo[3',2',1':8,1][1,4]benzazaborino[2,3,4-kl]phenazaborine
Classification or Family	Triarylamine derivatives, Tryphenylboron, Blue dopant, Multiresonance thermally activated delayed fluorescent (MR-TADF), Sublimed materials.

Product Details

Purity	Sublimed* >99% (HPLC)
Melting point	-
Appearance	Yellow powder/crystals

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

Chemical Structure

Device Structure(s)

Device structure	ITO/PEDOT:PSS (40 nm)/CzAcSF:5 wt.% CzBN (50 nm)/DPEPO (10 nm)/TmPyPB (35 nm)/Liq (1 nm)/Al [1]
Colour	Sky-blue emission at 482 nm with an FWHM of 36 nm
Max Current Efficiency	24.3 cd/A
Max Power Efficiency	15.9 lm/W
Max EQE	14.7%

Device structure	ITO/HAT-CN (10 nm)/Tris-PCz (30 nm)/mCBP (5 nm)/mCBP:20 wt% TPh2Cz2DPhCzBN:0.5 wt% CzBN* (30 nm)/SF3-TRZ (10 nm)/SF3-TRZ:30 wt% Liq (20 nm)/Liq (2 nm)/Al (100 nm) [2]
Colour	Sky-blue emission (0.135, 0.312) at 480 nm with an FWHM of 34 nm
Max. Luminescence	49,933 cd/m²
Max Current Efficiency	38.3 cd/A
Max Power Efficiency	40.1 lm/W
Max EQE	20.6%

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

MSDS Documentation

CzBN MSDS Sheet

Literature and Reviews

Solution-processed multi-resonance organic light-emitting diodes with high efficiency and narrowband emission, S. Xu et al., Chinese Chem. Lett., 32, 1372–1376 (2021); DOI: 0.1016/j.cclet.2020.10.022.
Investigating HOMO Energy Levels of Terminal Emitters for Realizing High-Brightness and Stable TADF-Assisted Fluorescence Organic Light-Emitting Diodes, Adv. Electron. Mater., Y. Lee et al., 7 (4), 2001090 (2021); DOI: 10.1002/aelm.202001090.
Narrowband Emissive Thermally Activated Delayed Fluorescence Materials, H. Kim et al., Adv. Opt. Mater., 10, 2201714 (2022); DOI: 10.1002/adom.202201714.

Tailor-Made Multi-Resonance Terminal Emitters toward Narrowband, High-Efficiency, and Stable Hyperfluorescence Organic Light-Emitting Diodes, Y. Lee et al., Adv. Opt. Mater., 10 (17), 2200682 (2022); DOI: 10.1002/adom.202200682.
Anti-Stokes Luminescence in Multi-Resonance-Type Thermally-Activated Delayed Fluorescence Molecules, S. Kohata et l., Angew. Chem. Int. Ed., 135 (44), e202312326 (2023); DOI: 10.1002/ange.202312326.