Advanced Optical Materials,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 16, 2024
Abstract
Cr
3+
‐doped
near‐infrared
(NIR)
phosphors
have
attracted
significant
attention
in
recent
years.
Despite
this,
achieving
high‐performance
NIR
with
broadband
emission
and
excellent
thermal
stability
remains
a
considerable
challenge.
This
study
presents
Lu
3
Ga
5
O
12
:Cr
,
which
demonstrates
tunable
peak
ranging
from
705
to
759
nm
an
increased
full‐width
at
half‐peak
maximum
(FWHM)
46
139
by
substituting
the
[Mg
2+
‐Ge
4+
]
chemical
unit
for
[Ga
‐Ga
unit.
Additionally,
MgGa
GeO
Yb
energy
transfer
channel
(Cr
‐Yb
)
is
constructed.
Under
blue
light
excitation,
characteristic
peaks
of
(600–900
nm)
(900–1100
are
observed
simultaneously.
However,
band
between
850
900
relatively
weak,
resulting
discontinuous
spectrum.
To
address
Nd
proposed,
exhibit
continuous
FWHM
253
internal
quantum
efficiency
47.3%.
The
luminescence
intensity
retains
81%
its
room
temperature
value
even
423
K.
Combining
this
new
phosphor
LED
chip
results
portable
source
potential
applications
non‐destructive
detection,
information
encryption,
bio‐imaging,
remote
control.
work
offers
novel
perspective
developing
phosphors.
Abstract
Even
though
there
have
been
significant
advancements
in
the
development
of
Cr
3+
‐activated
near‐infrared
(NIR)
phosphors,
challenge
still
remains
to
develop
highly
efficient
and
thermally
stable
NIR
phosphors.
Here,
Ca
4‐x
Zn
x
HfGe
3
O
12
:0.03Cr
solid
solution
phosphors
with
834–806
nm
emission
are
constructed
by
substituting
2+
for
,
thereby
facilitating
formation
[ZnO
6
]
luminescence
site.
The
coexistence
[HfO
[Zn/CaO
centers
is
confirmed
through
DFT
calculation,
time‐resolved
photoluminescence
(TRPL)
spectroscopy,
low‐temperature‐photoluminescence
(77
K)
spectroscopy.
effectively
resolves
issue
lattice
mismatch
between
.
Furthermore,
simultaneous
enhancement
intensity
thermal
stability
realized
a
synergistic
combination
distortion
rigidity
enhancement.
By
optimizing
substitution
concentration
internal
quantum
efficiency
(IQE)
92%
an
external
(EQE)
29%
finally
achieved.
Meanwhile,
also
enhanced
from
59%@400
K
(x
=
0)
81%@400
0.8).
developed
phosphor‐converted
light‐emitting
diodes
(pc‐LEDs)
exhibit
promising
prospects
fields
security,
biomedicine,
non‐destructive
testing
rapid
identification.
Advanced Materials,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Nov. 3, 2024
Abstract
Ultrabright
broadband
near‐infrared
(NIR)
phosphor‐converted
laser
diode
(pc‐LD)
as
a
light
source
is
increasingly
essential
for
improving
the
sensitivity
and
spatial
resolution
of
intelligent
NIR
spectroscopy
technologies.
However,
performance
pc‐LD
greatly
hindered
by
low
external
quantum
efficiency
(EQE)
poor
thermal
resistance
phosphor
materials.
Herein,
highly
stable
phosphor‐in‐ceramic
(PiC)
film
deposited
on
high
conductivity
substrate,
in
which
NIR‐emitting
Ca
3
MgHfGe
O
12
:Cr
3+
incorporated
into
glass‐crystallized
Ga
2
Ge
ceramic
matrix,
along
with
formation
new
type
PiC
composite
material
efficiency,
absorbance,
conductivity,
designed
prepared.
The
obtained
exhibits
an
impressive
EQE
57.7%,
17.1
W
m
−1
K
,
wheel
demonstrates
emission
exceeding
5
when
excited
450
nm
laser.
Finally,
groundbreaking
electrically
driven
device
based
achieves
1.6
output,
enabling
multiple
applications
archaeology
night
vision
imaging.
This
work
paves
way
advancing
sources
diverse
range
photonic
applications.
Abstract
Near‐infrared
phosphor‐converted
light‐emitting
diodes
(NIR
pc‐LEDs)
are
regarded
one
of
the
most
promising
light
sources
for
food
analysis,
plant
growth,
bioimaging,
night
vision,
and
so
on.
Cr
3+
‐activated
NIR
phosphors
have
garnered
increasing
attention
due
to
their
exceptional
photoluminescence
properties
pc‐LED.
However,
them
suffer
from
poor
thermal
stability
or
low
efficiency
which
limits
large‐scale
application.
Herein,
a
novel
Sr
3
MgGe
5
O
14
:
(SMGO:
)
phosphor
is
presented,
exhibits
broadband
emission
ranging
range
650–1000
nm
with
peak
at
735
nm.
SMGO:
0.005Cr
demonstrates
an
almost
near‐unity
internal
quantum
(99.4%)
excellent
quenching
performance
(
I
423
K
/I
298
=
86%).
First‐principles
theory
calculation
indicates
that
ions
preferentially
occupy
[Ge2/MgO
4
]
[Ge3O
sites
high
doping
concentration
within
SMGO
host,
illustrating
mechanism.
Furthermore,
pc‐LED
manufactured
by
utilizing
445
blue
LED
chip,
output
power
140.5
mW
photoelectric
conversion
15.5%
300
mA.
Potential
applications
growth
detection
several
mental
also
demonstrated,
demostrates
its
application
in
growth.
Abstract
Developing
tunable
broadband
near‐infrared
(NIR)
fluorescent
materials
with
outstanding
luminescence
properties
and
superior
thermal
robustness
remains
a
significant
challenge
for
next‐generation
intelligent
NIR
light
sources.
Herein,
high‐performance
large‐scale
NIR‐emitting
garnet‐type
phosphor,
SrLu
2
Al
3
ScSiO
12
:Cr
3+
(SLASSO:Cr
),
is
presented.
Upon
450
nm
blue
excitation,
SLASSO:1%Cr
phosphor
yields
emission
full
width
at
half
maximum
of
108
prominent
sharp
peak
694
superimposed
on
radiation,
which
attributed
to
the
co‐occupation
Cr
ions
dominant
[AlO
6
]
octahedral
site
(Cr1
site)
subordinate
[ScO
(Cr2
site).
Remarkably,
as
⁺
content
increases,
red‐shift
in
wavelength
spanning
from
785
bandwidth
broadening
89
152
are
observed,
stems
weakening
crystal
field
strength
energy
redistribution
within
Cr1
Cr2
centers
regulated
by
formation
local
‐Cr
ion
pairs.
Notably,
optimal
sample
boasts
an
excellent
internal
quantum
efficiency
89.4%
exceptional
stability
(97.6%@423
K).
Additionally,
fabricated
phosphor‐converted
light‐emitting
diode
devices
demonstrate
promising
multi‐functional
applications,
including
plant
cultivation,
night
vision,
bioimaging
non‐destructive
detection.
Inorganic Chemistry,
Journal Year:
2024,
Volume and Issue:
63(19), P. 8899 - 8907
Published: May 2, 2024
Given
the
escalating
significance
of
near-infrared
(NIR)
spectroscopy
across
industries,
agriculture,
and
various
domains,
there
is
an
imminent
need
to
address
development
a
novel
generation
intelligent
NIR
light
sources.
Here,
series
Cr3+-doped
BaLaMgNbO6
(BLMN)
ultrabroadband
phosphor
with
coverage
range
650–1300
nm
were
developed.
The
emission
peak
locates
at
830
full
width
half
maximum
210
nm.
This
originates
from
4T2→4A2
transition
Cr3+
simultaneous
occupation
[MgO6]
[NbO6]
octahedral
sites
confirmed
by
low
photoluminescence
spectra
(77–250
K),
time-resolved
spectra,
electron
paramagnetic
resonance
spectra.
fluxing
strategy
improves
luminescence
intensity
thermal
stability
BLMN:0.02Cr3+
phosphors.
internal
quantum
efficiency
(IQE)
51%,
external
(EQE)
can
reach
33%,
be
maintained
60%@100
°C.
Finally,
we
successfully
demonstrated
application
BLMN:Cr3+
in
qualitative
analysis
organic
matter
food
freshness
detection.
