Abstract
Broadband
near‐infrared
(NIR)
phosphor‐converted
light‐emitting
diodes
are
next‐generation
smart
NIR
light
sources.
However,
the
phosphor
suffers
from
serious
thermal
quenching
(TQ),
resulting
in
efficiency
reduction
and
spectral
shift.
Here,
a
novel
strategy
is
realized
to
suppress
TQ
by
minimizing
bond
angle
distortion,
completely
different
conventional
suppression
approach
through
length
variation.
Li(Sr
1−
x
Ca
)AlF
6
:Cr
3+
taken
as
an
example
which
rotation
between
two
parallel
fluorine
planes
perpendicular
C
3
axis
[AlF
]
octahedron
found
dominate
TQ.
Increasing
0
1
reduces
amplitude
of
16.17°
5.06°,
weakening
electron–phonon
coupling
and,
consequently,
raising
temperature
significantly
320
570
K.
This
mechanism
elucidated
both
theoretical
calculations
spectroscopic
studies.
The
findings
open
new
horizon
for
exploration
thermally
stable
phosphors.
Chemistry of Materials,
Journal Year:
2022,
Volume and Issue:
34(18), P. 8418 - 8426
Published: Sept. 15, 2022
Broadband
near-infrared
(NIR)
light
source
based
on
phosphor-converted
light-emitting-diode
(pc-LED)
is
crucial
for
applications
in
medical
diagnosis,
food
quality
analysis,
and
night
vision
fields,
motivating
the
development
of
highly
efficient
thermal
robust
NIR
phosphor
materials.
Herein,
a
novel
Cr3+-doped
garnet
Y3In2Ga3O12:Cr3+
emerges
from
fundamental
study
Ln3In2Ga3O12
(Ln
=
La,
Gd,
Y,
Lu)
family.
Upon
450
nm
excitation,
this
material
presents
broadband
emission
covering
650–1100
with
peak
located
at
760
full
width
half
maximum
125
nm.
This
also
possesses
an
ultrahigh
internal
quantum
efficiency
(IQE
91.6%)
absorption
(AE
46.6%),
resulting
external
as
high
42.7%.
Moreover,
intensity
150
°C
maintains
100%
initial
intensity,
showing
rare
zero-thermal-quenching
property.
Fabricating
pc-LED
device
by
using
material,
excellent
output
power
68.4
mW
photoelectric
15.9%
under
mA
driving
current
can
be
obtained,
which
exhibits
much
better
performance
than
devices
fabricated
some
reported
Therefore,
work
not
only
provides
ultraefficient
thermally
spectroscopy
application
but
contributes
to
foundation
design
rules
materials
performance.
ACS Applied Materials & Interfaces,
Journal Year:
2023,
Volume and Issue:
15(27), P. 32580 - 32588
Published: June 29, 2023
Blue
InGaN
chip-pumped
short-wave
infrared
(SWIR)
emitters
have
aroused
tremendous
attention
and
shown
emerging
applications
in
diverse
fields
such
as
healthcare,
retail,
agriculture.
However,
discovering
blue
light-emitting
diode
(LED)-pumped
SWIR
phosphors
with
a
central
emission
wavelength
over
1000
nm
remains
significant
challenge.
Herein,
we
demonstrate
the
efficient
broadband
luminescence
of
Ni2+
by
simultaneously
incorporating
Cr3+
ions
into
MgGa2O4
lattice,
sensitizer
emitter.
Because
strong
light
absorption
high
energy
transfer
efficiency
to
Ni2+,
obtained
MgGa2O4:Cr3+,
show
intense
peak
at
1260
full
width
half
maximum
(FWHM)
222
under
excitation
light.
The
optimized
phosphor
presents
an
ultra-high
photoluminescence
quantum
96.5%
outstanding
thermal
stability
(67.9%@150
°C).
A
source
has
been
fabricated
through
combination
prepared
commercial
450
LED
chip,
delivering
radiant
power
14.9
mW
150
mA
input
current.
This
work
not
only
demonstrates
feasibility
developing
high-power
using
converter
technology
but
also
new
insights
importance
technology.
Chemistry of Materials,
Journal Year:
2023,
Volume and Issue:
35(3), P. 1432 - 1439
Published: Jan. 27, 2023
To
promote
the
development
of
near-infrared
(NIR)
light
sources
in
optoelectronic
and
biomedical
applications,
discovery
NIR-emitting
phosphor
materials
their
design
principles
are
essential.
Herein,
we
report
a
novel
Eu2+-activated
broadband
phosphor,
BaSrGa4O8:Eu2+,
which
features
multisite
occupation
due
to
Ba/Sr
oxygen
site
occupancy
disorder.
With
an
increase
atomic
ratio
from
1:1
1.7:0.3,
Eu2+
emission
band
maximum
red-shifts
670
775
nm,
along
with
enlargement
full
width
at
half-maximum
(FWHM)
140
230
nm.
The
underlying
mechanism
for
structure–property
relationship
is
elucidated
using
density
functional
theory
calculations.
application
NIR
phosphor-converted
light-emitting
diodes
(pc-LEDs)
demonstrated,
showing
potential
night-vision
technology.
Our
results
can
initiate
further
exploitation
host
structural
disorder
toward
luminescence
applications
pc-LEDs.
Inorganic Chemistry Frontiers,
Journal Year:
2023,
Volume and Issue:
10(7), P. 2197 - 2205
Published: Jan. 1, 2023
Enhanced
and
broadened
NIR
luminescence
was
realized
in
a
Gd
2−
x
Al
GaSbO
7
:Cr
3+
phosphor
by
→
cation
substitution.
Its
application
as
an
emitting
converter
for
LEDs
confirmed.
Advanced Materials,
Journal Year:
2024,
Volume and Issue:
36(21)
Published: Feb. 21, 2024
Near-Infrared
(NIR)
light
emitting
metal
halides
are
emerging
as
a
new
generation
of
optical
materials
owing
to
their
appealing
features,
which
include
low-cost
synthesis,
solution
processability,
and
adjustable
properties.
NIR-emitting
perovskite-based
light-emitting
diodes
(LEDs)
have
reached
an
external
quantum
efficiency
(EQE)
over
20%
device
stability
10,000
h.
Such
results
sparked
interest
in
exploring
NIR
halide
emitters.
In
this
review,
several
different
types
halides,
including
lead/tin
bromide/iodide
perovskites,
lanthanide
ions
doped/based
double
low
dimensional
hybrid
Bi
ACS Applied Materials & Interfaces,
Journal Year:
2024,
Volume and Issue:
16(23), P. 30185 - 30195
Published: May 31, 2024
Broadband
near-infrared
(NIR)
phosphor-converted
light-emitting
diodes
(pc-LEDs)
hold
promising
potential
as
next-generation
compact,
portable,
and
intelligent
NIR
light
sources.
Nonetheless,
the
lack
of
high-performance
broadband
phosphors
with
an
emission
peak
beyond
900
nm
has
severely
hindered
development
widespread
application
pc-LEDs.
This
study
presents
a
strategy
for
precise
control
energy-state
coupling
in
spinel
solid
solutions
composed
MgxZn1–xGa2O4
to
tune
emissions
Cr3+
activators.
By
combining
crystal
field
engineering
heavy
doping,
Cr3+–Cr3+
ion
pair
from
4T2
state
is
unlocked,
giving
rise
unusual
spanning
650
1400
maximum
913
full
width
at
half-maximum
(fwhm)
213
nm.
Under
optimal
Mg/Zn
ratio
4:1,
sample
achieves
record-breaking
performance,
including
high
internal
external
quantum
efficiency
(IQE
=
83.9%
EQE
35.7%)
excellent
thermal
stability
(I423
K/I298
K
75.8%).
Encapsulating
as-obtained
into
prototype
pc-LEDs
yields
overwhelming
output
power
124.2
mW
driving
current
840
mA
photoelectric
conversion
(PCE)
10.5%
30
mA,
rendering
performance
imaging
applications.
Inorganic Chemistry Frontiers,
Journal Year:
2024,
Volume and Issue:
11(6), P. 1668 - 1682
Published: Jan. 1, 2024
Four
design
strategies
for
modulating
the
luminescence
thermal
quenching
properties
of
Bi
3+
-activated
phosphors
are
proposed:
(1)
defect
engineering;
(2)
structural
modulation;
(3)
lattice
structure
rigidity;
and
(4)
energy
transfer.
Materials Horizons,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Jan. 1, 2024
A
record-breaking
anti-thermal
quenching
of
broadband
NIR
emission
(198%@543
K)
is
achieved
in
a
Cr
3+
-activated
garnet
phosphor
via
excited-state
population
optimization.
