Abstract
Long‐wavelength
near‐infrared
(NIR)
phosphors
(1000–2000
nm)
have
shown
great
promise
in
intelligent
NIR
spectroscopy
technology
fields.
However,
developing
capable
of
directly
absorbing
blue
light
and
emitting
over
1000
nm
still
remains
a
significant
challenge.
Here,
series
ultra‐broadband
with
emission
peaks
longer
than
1500
is
achieved
by
incorporating
single
activator
Ni
2+
ion
into
ALaMgMO
6
(A
=
Ca,
Sr,
Ba;
M
Sb,
Nb,
Ta)
double
perovskite
hosts.
Significantly,
through
composition
modulation
strategy,
the
designed
exhibit
an
intense
absorption
band
centered
at
440
nm,
making
these
mono‐doped
pumped
commercial
LED
chips
without
strictly
introducing
sensitized
ions
or
energy
transfer
process.
The
origination
effective
blue‐light
excitable
NIR‐II
to
NIR‐III
phosphor
unraveled
Rietveld
structural
refinement
local
symmetry
analysis.
Additionally,
developed
demonstrated
potential
spectroscopic
analysis,
night‐vision
technology,
non‐destructive
visualization,
information
encryption
identification.
This
work
provides
feasible
strategy
solve
problem
that
‐doped
cannot
be
can
promote
development
more
long‐wavelength
materials
for
multiple
photonic
applications.
Advanced Optical Materials,
Journal Year:
2023,
Volume and Issue:
11(21)
Published: June 7, 2023
Abstract
Cr
3+
‐activated
Gd
3
Ga
5
O
12
garnet
(GGG:Cr
)
near‐infrared
(NIR)
phosphors
have
shown
promising
applications
in
regulating
plant
growth.
However,
the
low
external
quantum
efficiency
(EQE)
results
a
wall‐plug
(WPE)
of
phosphor‐converted
light‐emitting
diodes
(pc)‐LEDs
only
≈15%.
Herein,
an
easy
strategy
to
improve
luminescent
properties
GGG:Cr
phosphor
is
reported.
Through
optimization
synthesized
technology,
EQE
enhanced
43.6%.
Remarkably,
fabricated
pc‐LEDs
achieve
WPE
as
high
34.3%.
These
demonstrate
significant
advancement
development
and
NIR
materials
pc‐LED
devices.
Advanced Powder Materials,
Journal Year:
2024,
Volume and Issue:
3(3), P. 100186 - 100186
Published: March 6, 2024
Cr3+-activated
near-infrared
(NIR)
phosphors
are
key
for
NIR
phosphor-converted
light
emitting
diodes
(NIR
pc-LED).
While,
the
site
occupancy
of
Cr3+
is
one
debates
that
have
plagued
researchers.
Herein,
Y2Mg2Al2Si2O12
(YMAS)
with
multiple
cationic
sites
chosen
as
host
to
synthesize
YMAS:
xCr3+
phosphors.
In
YMAS,
ions
occupy
simultaneously
Al/SiO4
tetrahedral,
Mg/AlO6
octahedral,
and
Y/MgO8
dodecahedral
which
form
three
luminescent
centers
named
Cr1,
Cr2,
Cr3,
respectively.
Cr1
Cr2
relate
an
intermediate
crystal
field,
transitions
2E→4A2
4T2→4A2
occurring
simultaneously.
As
concentration
increases,
transition
becomes
more
pronounced
in
resulting
a
red-shift
broadband
emission.
Cr3
consistently
behaves
weak
field
exhibits
broad
long-wavelength
Wide-range
emission
centering
at
745
nm
realized
0.03Cr3+
phosphor.
This
phosphor
has
high
internal
quantum
efficiency
(IQE
=
86%)
satisfying
luminescence
thermal
stability
(I423
K
70.2%).
Using
this
phosphor,
pc-LEDs
56.6
mW@320
mA
optical
output
power
packaged
applied.
Present
study
not
only
demonstrates
multi-site
certain
oxide
but
also
provides
reliable
approach
via
choosing
diverse
local
environments
achieve
Advanced Optical Materials,
Journal Year:
2024,
Volume and Issue:
12(17)
Published: March 2, 2024
Abstract
The
near‐infrared
(NIR)
persistent
luminescence
(PersL)
materials
have
attracted
widespread
attention
owing
to
the
unique
self‐sustained
light
with
good
penetrability.
Currently,
most
of
reported
NIR
PersL
are
activated
by
Cr
3+
.
Considering
potential
toxicity
chromium
ions,
there
is
an
urgent
requirement
explore
‐free
phosphors.
Herein,
a
novel
phosphor
Sr
2
LuSbO
6
:Fe
(SLSO:Fe
)
prepared
and
its
properties
systematically
studied.
Fe
‐activated
exhibits
long‐wavelength
emission
band
centered
at
890
nm
110
full‐width
half
maximum
(FWHM),
can
last
over
18
h.
shows
excellent
stability
even
after
being
dispersed
in
solutions
different
environments
for
7
days.
Furthermore,
emitted
penetrate
cm
thickness
beef,
evidencing
penetration
property.
This
work
provides
based
on
technological
applications
also
contributes
accelerate
development
new‐generation
‐doped
toward
versatile
applications.
Abstract
Near‐infrared
(NIR)
phosphor‐converted
light‐emitting
diodes
(pc‐LEDs)
are
considered
as
promising
next‐generation
light
sources
for
optoelectronic
and
biomedical
applications.
Nevertheless,
NIR
phosphors
with
large
bandwidths,
long
emission
peaks,
high
external
quantum
efficiencies
(EQEs)
valuable
thermal
stabilities
challenging
to
develop.
Herein,
this
study
reports
a
novel
gallium
germanate
host,
Ga
3
Al
Ge
2
O
13
(GAGO),
bandgap
rigid
host
lattice
Cr
3+
ion
doping.
The
blue
LED
excitable
GAGO:0.012Cr
phosphor
can
produce
broadband
maximum
intensity
at
816
nm
full‐width
half‐maximum
(FWHM)
of
187
nm.
Notably,
the
also
exhibits
an
excellent
EQE
35.8%
perfect
stability
(I
423
K
/I
298
=
67.4%).
Moreover,
attractive
afterglow
duration
more
than
24
h
is
achieved
in
GAGO:0.004Cr
phosphor.
type
origin
traps
discussed,
possible
persistent
luminescent
(LPL)
mechanism
proposed.
Finally,
pc‐LED
based
on
fabricated.
results
demonstrate
that
obtained
show
great
potential
use
night
vision,
nondestructive
detection,
bioimaging
information
encryption.
This
provides
new
insight
into
development
materials
efficiency,
good
extraordinary
performance.
Advanced Optical Materials,
Journal Year:
2023,
Volume and Issue:
11(23)
Published: July 26, 2023
Abstract
Applications
in
near‐infrared
(NIR)
have
been
explored
significantly
many
fields,
including
bioimaging,
night
vision,
plant
growth,
and
chemical
analysis.
Different
emission
profiles
are
required
within
the
same
industry.
Developing
luminescent
materials
with
different
tuning
methods
is
reliable
for
controlling
NIR
regions
(NIR‐I,
700–1000
nm;
NIR‐II,
1000–1700
nm).
Spinel
phosphors
promising
candidates
due
to
their
ability
modulate
crystal
field.
Understanding
parameters
that
influence
degree
of
inversion
spinel
compounds
crucial
harness
variability
structure.
Cr
3+
Ni
2+
ideal
activators
NIR‐I
NIR‐II
emissions,
respectively.
However,
there
a
need
emit
region
when
excited
by
visible
light.
Although
energy
transfer
method
combining
two
considered,
this
review
focuses
on
types
structures,
discussing
common
strategies
tune
host
The
goal
achieve
desired
shift
broadness
entire
spectrum,
highlighting
importance
spectrum
practical
applications.
Abstract
Near‐infrared
(NIR)
II
region
(1000–1700
nm)
lighting
sources
possess
special
potential
for
temperature
sensing
and
quantitative
composition
analysis.
However,
it
is
a
challenge
to
tune
the
luminescence
toward
such
long
wavelength
NIR‐II
emission.
Herein,
Cr
4+
ions
occupation
designed
verified
in
olivine‐type
CaYGaO
4
as
[CrO
]
tetrahedron
by
site
occupancy
confinement.
Under
620
nm
red
light
excitation,
phosphors
display
broadband
emission
centered
at
1330
with
full
width
half
maximum
(FWHM)
of
233
nm,
resulting
from
spin‐allowed
3
T
2
A
transition
d
symmetry.
The
optical
thermometry
application
demonstrated
decoding
spectral
shift
decay
times
varying
temperature,
relative
sensitivities
are
5.82%
0.78%
K
−1
,
respectively.
Furthermore,
flexible
film
containing
:Cr
fabricated
implement
non‐invasive
detections
fillet
NH
concentration
ammonia.
This
work
represents
step
developing
next‐generation
materials
widens
detection
applications.
