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Title: Eliminating nonradiative decay in Cu(I) emitters: >99% quantum efficiency and microsecond lifetime
Luminescent complexes of heavy metals such as iridium, platinum, and ruthenium play an important role in photocatalysis and energy conversion applications as well as organic light-emitting diodes (OLEDs). Achieving comparable performance from more–earth-abundant copper requires overcoming the weak spin-orbit coupling of the light metal as well as limiting the high reorganization energies typical in copper(I) [Cu(I)] complexes. Here we report that two-coordinate Cu(I) complexes with redox active ligands in coplanar conformation manifest suppressed nonradiative decay, reduced structural reorganization, and sufficient orbital overlap for efficient charge transfer. We achieve photoluminescence efficiencies >99% and microsecond lifetimes, which lead to an efficient blue-emitting OLED. Photophysical analysis and simulations reveal a temperature-dependent interplay between emissive singlet and triplet charge-transfer states and amide-localized triplet states.  more » « less
Award ID(s):
1661518
PAR ID:
10092299
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Science
Volume:
363
Issue:
6427
ISSN:
0036-8075
Page Range / eLocation ID:
601 to 606
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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