New polycyclic aromatic hydrocarbon dopants for red organic electroluminescent devices

Abstract

Two new anthracene derivatives with red emission have been synthesized. The materials were characterized with photoluminescence spectroscopy, and showed emission peaking at over 600 nm. Organic light-emitting devices were fabricated by using these derivatives as dopants. The devices have a maximum efficiency of 0.6 cd A 21 and an emission peak at 617 nm. The results of color tuning and fluorescent yield enhancement for anthracene derivatives are presented.

Synthesis of Nitrogen‐Containing Rubicene and Tetrabenzopentacene Derivatives

“…By comparison, the spectrum obtained for 9 was broadened and red-shifted (presumably due to the molecules expanded aromatic system), with prominent absorption peaks at 400 nm and 524 nm ( Figure 2). Likewise,w ef ound that the spectra for 5 and 10 were similar to the ones reported for tetrabenzopentacene [36,37,44] and other pentacene derivatives. [7,8,26,27] The spectrum obtained for 5 featured acluster of three characteristic absorption peaks at 555 nm, 600 nm, and 650 nm ( Figure 2).…”

“…Although these molecules were synthesized > 60 years ago,their nitrogen-containing analogues have never been reported (to the best of our knowledge), and tetrabenzopentacene is even still prepared via arelatively limited and harsh method. [44] Moreover, variants of these polycyclic aromatic hydrocarbons (PAHs) have exhibited promising functionality in organic electronic devices,i ncluding light emitting diodes,p hotovoltaics,a nd transistors. [44][45][46] Consequently,w er egarded nitrogen-containing rubicenes and tetrabenzopentacenes as challenging and exciting synthetic targets.…”

1,8-Naphthalimides for non-doping OLEDs: the tunable emission color from blue, green to red

“…Recently, dot matrix OLED panels with blue and green colors became commercially available and a full color quarter video graphics array (320 × 240 dots) panel was also demonstrated [8]. However, red emissive materials with high fluorescent quantum yields are not as common as blue or green materials in OLED applications [9]. There were only a few organic compounds reported to have red emissions, including pyran-containing compounds [10], europium chelate complexes [11], and porphyrin compounds [12][13][14][15].…”

Synthesis of Nitrogen‐Containing Rubicene and Tetrabenzopentacene Derivatives

“…For the design of our nitrogen‐doped compounds, we sought inspiration from the classic all‐carbon rubicene and tetrabenzopentacene motifs (Figure b). Although these molecules were synthesized >60 years ago, their nitrogen‐containing analogues have never been reported (to the best of our knowledge), and tetrabenzopentacene is even still prepared via a relatively limited and harsh method . Moreover, variants of these polycyclic aromatic hydrocarbons (PAHs) have exhibited promising functionality in organic electronic devices, including light emitting diodes, photovoltaics, and transistors .…”