In:
Chemistry – A European Journal, Wiley, Vol. 23, No. 23 ( 2017-04-24), p. 5448-5458
Abstract:
A novel series of monodisperse star‐shaped ladder‐type oligo( p ‐phenylene)s, named as TrL ‐n ( n =1–3), have been explored. Their thermal and electrochemical properties, fluorescence transients, photoluminescence quantum yields, density functional theory calculations, electroluminescence (EL) and amplified spontaneous emission (ASE) properties have been systematically investigated to unravel the molecular design on optoelectronic properties. The resulting materials showed excellent structural perfection, free of chemical defects, and exhibited great thermal stability ( T d : 404–418 °C and T g : 147–184 °C) and amorphous glassy morphologies. Compared with their corresponding linear counterparts FL ‐m ( m =1–3), TrL ‐n showed only little bathochromic shifts (5–12 nm) for the absorption maxima λ max in both solution and films. The star‐shaped ladder‐type compounds exhibited enhanced optical stability and suppressed low‐energy emission. Their EL spectra exhibited excellent stability with increasing the driving voltage from 6 to 12 V. Moreover, superior low ASE thresholds were recorded for TrL ‐n compared with FL ‐m . Rather low ASE threshold (29 nJ per pulse or 1.60 μJ cm −2 ) was recorded for TrL‐3, demonstrating their promising potential as excellent gain media. This study provides a novel design concept to develop monodisperse star‐shaped ladder‐type materials with excellent structural perfection, which are vital for shedding light on exploring robust organic emitters for optoelectronic applications.
Type of Medium:
Online Resource
ISSN:
0947-6539
,
1521-3765
DOI:
10.1002/chem.201605885
Language:
English
Publisher:
Wiley
Publication Date:
2017
detail.hit.zdb_id:
1478547-X