Optics Letters,
Journal Year:
2024,
Volume and Issue:
50(2), P. 634 - 634
Published: Dec. 17, 2024
Near-infrared
(NIR)
phosphor-converted
light-emitting
diode
(pc-LED)
has
emerged
as
the
most
promising
NIR
light
source,
highlighting
importance
of
exploring
phosphors
with
excellent
efficiency
and
sufficient
spectral
coverage.
Herein,
a
garnet
Na
2
CaHf
Ge
3
O
12
:Cr
3+
phosphor
an
internal
quantum
(IQE)
79.2%
been
developed,
which
exhibits
relatively
long
wavelength
emission
peak
at
830
nm
full
width
half
maximum
(FWHM)
144
nm.
Moreover,
can
be
gradually
tuned
to
903
intensity
maintaining
over
60%
utilizing
chemical
unit
co-substitution
strategy.
Thus,
developed
material
in
this
work
wide-range
tunability,
being
for
multifunctional
spectroscopy
applications.
Inorganic Chemistry,
Journal Year:
2024,
Volume and Issue:
63(28), P. 12886 - 12893
Published: July 1, 2024
Inorganic
materials
doped
with
chromium
(Cr)
ions
generate
remarkable
and
adjustable
broadband
near-infrared
(NIR)
light,
offering
promising
applications
in
the
fields
of
imaging
night
vision
technology.
However,
achieving
high
efficiency
thermal
stability
these
NIR
phosphors
poses
a
significant
challenge
for
their
practical
application.
Here,
we
employ
crystal
field
engineering
to
modulate
characteristics
Cr3+-doped
Gd3Ga5O12
(GGG).
The
Gd3MgxGa5–2xGexO12
(GMGG):7.5%
Cr3+
(x
=
0,
0.05,
0.15,
0.20,
0.40)
emission
are
developed
through
cosubstitution
Mg2+
Ge4+
Ga3+
sites.
This
strategy
also
effectively
reduces
strength
around
ions,
which
results
enhancement
photoluminescence
(PL)
full
width
at
half-maximum
(fwhm)
from
97
165
nm,
alongside
red
shift
PL
peak
an
intensity
up
2.3
times.
Notably,
behaviors
is
improved.
demonstrate
potential
biological
tissue
penetration
vision,
as
well
exceptional
scintillation
performance
scintillator
imaging.
research
paves
new
perspective
on
development
high-performance
technology
light-emitting
diodes
(LEDs)
X-ray
applications.
Journal of Materials Chemistry C,
Journal Year:
2024,
Volume and Issue:
12(34), P. 13268 - 13278
Published: Jan. 1, 2024
A
cation
site
modulation
strategy
is
proposed
to
regulate
the
emission
wavelength
of
Fe
3+
-activated
spinel
phosphors
with
superior
anti-quenching
properties.
AIP Advances,
Journal Year:
2024,
Volume and Issue:
14(5)
Published: May 1, 2024
With
the
development
of
white
light-emitting
diode
(LED)
technology,
near-infrared
(NIR)
phosphor-converted
(pc)
LED
is
becoming
a
new
emerging
light
source.
However,
due
to
lack
long
wavelength
components
phosphors,
application
NIR
pc-LED
restricted.
In
this
work,
continuous
ultra-broadband
emission
without
gap
in
850–950
nm
region
has
been
realized
Mg4Nb2O9
(MNO):Cr3+,
Yb3+
phosphor.
Meanwhile,
when
compared
MNO:Cr3+,
an
improved
internal
quantum
efficiency
(from
55.4%
72.6%)
and
thermal
stability
39%
63%
at
100
°C)
have
obtained
for
Yb3+,
which
attributed
combined
effect
efficient
energy
transfer
from
Cr3+
its
nearest
unique
levels
Yb3+.
The
performances
fabricated
devices
by
combining
with
460
chips
were
also
given,
results
demonstrate
that
phosphor
may
potential
practical
pc-LED.
Abstract
Far‐red
(FR)
and
near‐infrared
(NIR)
spectroscopy
technologies
have
attracted
extensive
attention.
How
to
obtain
luminescent
materials
suitable
FR‐NIR
phosphor‐converted
light‐emitting
diodes
(pc‐LEDs)
is
a
crucial
challenge.
Herein,
Si
3
N
4
‐substitution
strategy
employed
regulate
the
luminescence
of
Gd
Ga
5
O
12
:Cr
3+
(GGG:Cr
)
phosphors.
The
bandwidth
GGG:Cr
95
nm,
then
it
broadened
116
nm
due
‐substitution.
Furthermore,
at
423
K
thermal
stability
enhanced
98.7%
that
room
temperature,
which
higher
than
reported
92.7%@423
for
‐free
sample.
intensity
optimal
specimen
elevated
2.9
times
compared
with
sample
sintered
same
condition.
FR
pc‐LED
manufactured
by
using
optimized
sample,
its
output
power
47.1
mW
conversion
efficiency
15.9%
driven
100
mA.
This
work
paves
new
way
design
high‐performance
NIR
Inorganic Chemistry,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 15, 2025
The
portable
near-infrared
(NIR)
phosphor-converted
light-emitting
diodes
(pc-LEDs)
with
a
broad
spectrum
have
great
application
potential
in
information
encryption,
infrared
night
vision,
medical
imaging,
chemical
component
detection,
nondestructive
testing,
and
many
other
fields,
which
stable
efficient
ultrawide
NIR-emitting
phosphors
become
new
pursuit.
However,
the
low
luminescence
intensity
narrowband
emission
of
most
NIR
limit
their
applications.
Under
this
drive,
phosphor,
Li2MgTi2.99O8:0.01Cr3+
(LMT:0.01Cr3+),
TiO6
MgO6
octahedral
sites
for
Cr3+,
was
developed.
It
exhibits
79.28%
internal
quantum
efficiency
(IQE)
155
nm
full
width
at
half
maximum
(fwhm)
range
600∼1300
nm.
Based
on
weakened
crystal
field
strength
through
[In3+-In3+]
unit
to
cosubstitute
[Ti4+-Mg2+]
unit,
peak
red-shifted
from
751
772
nm,
fwhm
widening
205
Li2Mg0.98In0.04Ti2.97O8:0.01Cr3+phosphors
(LMIT:0.01Cr3+).
IQE
also
further
enhanced
85.02%
by
substituting
Mg2+
LMIT:0.01Cr3+
Zn2+,
increasing
index
lattice
distortion
center
get
Li2Mg0.92In0.04Zn0.06Ti2.97O8:0.01Cr3+
(LMIZT:0.01Cr3+).
pc-LED
devices
were
fabricated
combining
LMIZT:0.01Cr3+
phosphor
blue
LED
chip,
applications
evaluated,
showing
excellent
prospects
penetration
imaging
encryption.
Abstract
The
enduring
enigma
surrounding
the
near-infrared
(NIR)
emission
of
Mn
2+
continues
to
ignite
intense
academic
discussions.
Numerous
hypotheses
have
emerged
from
extensive
research
endeavors
explain
this
phenomenon,
such
as
formation
–Mn
ion
pairs,
occupying
cubically
coordinated
sites,
well
conjectures
positing
involvement
3+
oxidized
or
defects.
Despite
these
diverse
and
valuable
insights,
none
yet
achieved
broad
consensus.
In
study,
we
observed
prolonged
fluorescence
lifetimes
(~10
ms)
for
NIR
emissions
ions,
hinting
at
ions
high-symmetry
octahedral
sites
inherent
garnet
lattice.
This
inference
is
supported
by
corroborating
results
X-ray
absorption
fine
structure
analysis
first-principles
calculations.
crystal
field
similar
that
AlO
6
,
facilitates
splitting
d
–
energy
levels,
thereby
inducing
a
red-shift
in
spectrum
region
due
transition
4
T
1
(
G)
→
A
S)
isolated
.
Our
findings
not
only
offer
plausible
rationale
exhibited
other
-activated
phosphors
but
also
pave
definitive
route
towards
understanding
fundamental
mechanisms
responsible
ions.
