Angewandte Chemie,
Год журнала:
2024,
Номер
unknown
Опубликована: Дек. 3, 2024
Abstract
Achieving
high
efficiency
narrowband
near‐ultraviolet
(NUV)
emitters
in
organic
light
emitting
diode
(OLED)
is
still
a
formidable
challenge.
Herein,
proof‐of‐concept
hybridized
local
and
charge
transfer
(HLCT)
molecule,
named
ICz‐BO,
prepared
characterized,
which
both
multiresonant
(MR)
skeletons
are
integrated
via
conjugation
connection.
A
slightly
distorted
structure
weak
intramolecular
(CT)
interaction
between
two
MR
subunits
lead
to
high‐lying
reverse
intersystem
crossing
(h‐RISC)
channel
of
T
6
→
S
1
,
also
evidenced
by
experimental
calculated
results.
Impressively,
the
ICz‐BO
emitter
exhibits
outstanding
NUV
emission
at
404
nm
with
full‐width
half
maximum
28
toluene
solution.
The
solution
processable
OLED
shows
an
excellent
device
performance
recorded
external
quantum
12.01
%,
concomitant
extremely
low
y‐axis
Commission
Internationale
de
l’Éclairage
(CIE
y
)
value
0.031.
To
best
our
knowledge,
this
highest
reported
for
HLCT‐based
NUV‐OLEDs
date.
This
research
proves
that
skeleton
plays
positive
effect
on
hot
exciton
emitter,
provides
alternative
paradigm
developing
high‐efficiency
emitters.
ABSTRACT
Organic
light‐emitting
diodes
(OLEDs)
based
on
purely
organic
room‐temperature
phosphorescence
(RTP)
materials
often
encounter
issues
of
relatively
low
efficiency
and
spectral
instability.
To
overcome
these
limitations,
three
(arylthio)benzene
derivatives
(4S,
5S,
6S)
with
gradually
increased
RTP
component
are
designed
compared.
Theoretical
calculation
photophysical
investigation
reveal
that
the
fully
substituted
arylthio
effect
could
enhance
aggregation‐induced
phosphorescence,
enlarge
spin
orbital
coupling,
reduce
energy
gap
between
S
1
T
as
much
possible.
As
a
result,
6S
can
exhibit
single
spectra
in
films
high
up
to
76.7%,
its
doped
RTP‐OLED
furnishes
maximum
external
quantum
(EQE)
15.3%
ultra‐stable
brightness
raised
from
30
2000
cd
m
−2
.
Furthermore,
serving
sensitizer,
RTP‐sensitized‐fluorescent
OLEDs
fluorescence
dopant
TBRb
multiple
resonance
type
BN3
both
show
near
times
improvement
electroluminescence
performance,
EQE
values
11.3%
25.6%,
respectively.
These
results
demonstrate
feasibility
designing
advance
development
high‐performance
OLEDs.
Angewandte Chemie,
Год журнала:
2024,
Номер
unknown
Опубликована: Дек. 3, 2024
Abstract
Achieving
high
efficiency
narrowband
near‐ultraviolet
(NUV)
emitters
in
organic
light
emitting
diode
(OLED)
is
still
a
formidable
challenge.
Herein,
proof‐of‐concept
hybridized
local
and
charge
transfer
(HLCT)
molecule,
named
ICz‐BO,
prepared
characterized,
which
both
multiresonant
(MR)
skeletons
are
integrated
via
conjugation
connection.
A
slightly
distorted
structure
weak
intramolecular
(CT)
interaction
between
two
MR
subunits
lead
to
high‐lying
reverse
intersystem
crossing
(h‐RISC)
channel
of
T
6
→
S
1
,
also
evidenced
by
experimental
calculated
results.
Impressively,
the
ICz‐BO
emitter
exhibits
outstanding
NUV
emission
at
404
nm
with
full‐width
half
maximum
28
toluene
solution.
The
solution
processable
OLED
shows
an
excellent
device
performance
recorded
external
quantum
12.01
%,
concomitant
extremely
low
y‐axis
Commission
Internationale
de
l’Éclairage
(CIE
y
)
value
0.031.
To
best
our
knowledge,
this
highest
reported
for
HLCT‐based
NUV‐OLEDs
date.
This
research
proves
that
skeleton
plays
positive
effect
on
hot
exciton
emitter,
provides
alternative
paradigm
developing
high‐efficiency
emitters.
