Highly stable and efficient deep-red phosphorescent organic light-emitting devices using a phenanthroline derivative as an n-type exciplex host partner

Abstract

A new entry of nBPhen-based n-type exciplex host partner realizes high efficiency and highly stable deep red phosphorescent organic light-emitting devices with an emission peak wavelength of 670 nm, and maximum external quantum efficiency of 17%.

Effect of substitution position of dibenzofuran-terminated robust hole-transporters on physical properties and TADF OLED performances

“…To evaluate the performance of TnDBFBP derivatives, we fabricated 4CzIPN -based green TADF OLEDs with the following structure: [ITO (100 nm)/polymer buffer 12 (20 nm)/ NPD (10 nm)/ HTL (10 nm)/3,3′-di(9 H -carbazol-9-yl)-1,1′-biphenyl ( mCBP ): 13 20 wt% 4CzIPN (30 nm)/2-(3′-(dibenzo[ b , d ]thiophen-4-yl)-[1,10-biphenyl]-3-yl)-4,6-diphenyl-1,3,5-triazine ( DBF-TRZ ) 14 (10 nm)/2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline ( nBPhen ) (40 nm)/8-quinolinolato lithium ( Liq ) (2 nm)/Al (100 nm)]. Here, we used nBPhen as an ETL because this ETL is expected to realize longer lifetime 15 compared with previously used DPB . 7 The chemical structures and energy diagrams are shown in Fig.…”

Tetrapyridine/triphenyltriazine-conjugated electron transporters for low-power-consumption, high-stability phosphorescent OLEDs

“…The I p values were much deeper than those of the phenanthroline-based ETL nBPhen (−6.3 eV). 12 The optical energy gap ( E g ) was estimated from the UV-vis absorption spectra, and was determined to be 3.4 eV (Fig. S17, ESI†).…”

Unveiling the Aging Process of Organic Light‐Emitting Devices with Langevin and Hole Trap‐Assisted Recombination Exciplex Cohosts

“…This achievement indicates one of the most stable phosphorescent OLEDs amongst previous academic reports. [7,10,[20][21][22][23][24] It is worth noting that aging stability of the NPB:ETM-1 devices was more variational to the HTM:ETM ratios (Figure S5, Supporting Information), suggesting carrier balance and recombination profiles play significant roles on the electrical aging process.…”

“…When introducing exciplex cohosts to industrial applications, a long-term stability of devices is still one of the most challenging issues to satisfy rigid commercial demands, owing to chemical instabilities of organic materials. [7][8][9][10] Generally, deterioration of these molecules starts from chemical bond cleavages. [11,12] The generated fragments further react to adjacent excitons or charged carriers, generating exciton quenchers, non-radiative carrier recombination centers or charged carrier traps.…”