Nature Communications,
Journal Year:
2024,
Volume and Issue:
15(1)
Published: July 8, 2024
Solid-state
infrared-to-visible
photon
up-conversion
is
important
for
spectral-tailoring
applications.
However,
existing
systems
not
only
suffer
from
low
efficiencies
and
a
need
high
excitation
intensity,
but
also
exhibit
limited
selection
of
materials
complex
fabrication
processes.
Herein,
we
propose
sensitizer
with
bulk-heterojunction
structure,
comprising
both
an
energy
donor
acceptor,
triplet-triplet
annihilation
devices.
The
occurs
through
charge
separation
at
the
donor-acceptor
interface,
followed
by
formation
transfer
state
between
annihilator
following
spin
statistics.
ensures
efficient
generation
recombination.
Hence,
achieve
highly
solid-state
device
2.20%
efficiency
intensity
(10
mW
cm
Advanced Optical Materials,
Journal Year:
2022,
Volume and Issue:
10(19)
Published: July 10, 2022
Abstract
Numerous
reports
hitherto
show
that
the
photoluminescence
(PL)
properties
of
metal
nanoclusters
(NCs)
can
be
enhanced
by
alloying
cores.
In
particular,
biicosahedral
[Ag
x
Au
25−
(PPh
3
)
10
(SR)
5
Cl
2
]
2+
(abbreviated
as
Ag
hereafter;
with
PPh
=
triphenylphosphine;
SR
thiolate
ligand)
NCs
attract
significant
attention
because
their
PL
quantum
yield
is
improved
200
times
when
13
atoms
are
replaced
(
13).
this
contribution,
origin
in
system
and
its
remarkable
enhancement
investigated
on
basis
spectroscopic
investigations
behavior
quenching
an
organic
fluorophore,
finding
(i)
observed
phosphorescent;
(ii)
not
only
12
but
also
contribute
to
PL;
(iii)
replacing
central
vertex
atom
biicosahedron
causes
a
blue
shift
triplet
states,
which
suppresses
T
1
–S
0
intersystem
crossing
enhances
phosphorescence
emission.
Additionally,
results
single‐particle
spectroscopy
defocused
imaging
rotation
linearly
polarized
excitation
light
reveal
transition
dipole
moment
exists
long
axis
direction
biicosahedron.
Furthermore,
sensitize
molecular
triplets
efficiently
induce
red‐to‐blue
photon
upconversion
via
triplet–triplet
annihilation.
ACS Materials Au,
Journal Year:
2022,
Volume and Issue:
2(6), P. 641 - 654
Published: Aug. 7, 2022
The
process
of
photon
upconversion
promises
importance
for
many
optoelectronic
applications,
as
it
can
result
in
higher
efficiencies
and
more
effective
management.
Upconversion
via
triplet–triplet
annihilation
(TTA)
occurs
at
low
incident
powers
high
efficiencies,
requirements
integration
into
existing
devices.
Semiconductor
nanocrystals
are
a
diverse
class
triplet
sensitizers
with
advantages
over
traditional
molecular
such
energetic
tunability
minimal
energy
loss
during
the
sensitization
process.
In
this
Perspective,
we
review
current
progress
semiconductor
nanocrystal
sensitization,
specifically
focusing
on
nanocrystal,
ligand
shell
which
surrounds
solid-state
sensitization.
Finally,
discuss
potential
areas
improvement
could
efficient
systems
sensitized
by
nanocrystals.
Specifically,
focus
development
TTA
systems,
elucidation
transfer
mechanisms
from
to
transmitter
underpin
propose
novel
configurations
nanocrystal-sensitized
systems.
The Journal of Physical Chemistry Letters,
Journal Year:
2022,
Volume and Issue:
13(7), P. 1713 - 1718
Published: Feb. 14, 2022
Colloidal
semiconductor
nanocrystals
as
triplet
photosensitizers
are
characterized
by
a
negligible
intersystem
crossing
energy
loss
compared
to
that
of
traditional
molecular
sensitizers.
This
property
in
principle
allows
for
large
apparent
anti-Stokes
shift
sensitized
triplet-triplet
annihilation
photon
upconversion
(TTA-UC)
variety
applications.
In
previous
systems,
however,
this
advantage
is
largely
erased
the
associated
with
transfer
from
surface-anchored
transmitter
molecules.
Here
we
report
visible-to-ultraviolet
TTA-UC
473
355
nm,
corresponding
an
0.87
eV,
quantum
efficiency
reaches
4.5%
(normalized
at
100%).
The
system
consists
CsPbBr3
nanocrystal
sensitizers,
phenanthrene
transmitters,
and
diphenyloxazole
annihilators.
Time-resolved
spectroscopy
reveals
can
be
endothermic
yet
efficient
thanks
sizable
entropic
gain.
study
exemplifies
how
effects
harnessed
enhance
or
control
plethora
applications
photosensitizers.
Journal of the American Chemical Society,
Journal Year:
2022,
Volume and Issue:
144(8), P. 3527 - 3534
Published: Feb. 21, 2022
Leveraging
triplet
excitons
in
semiconductor
quantum
dots
(QDs)
concert
with
surface-anchored
molecules
to
produce
long-lifetime
thermally
activated
delayed
photoluminescence
(TADPL)
continues
emerge
as
a
promising
technology
diverse
areas
including
photochemical
catalysis
and
light
generation.
All
QDs
presently
used
generate
TADPL
QD/molecule
constructs
contain
toxic
metals
Cd(II)
Pb(II),
ultimately
limiting
potential
real-world
applications.
Here,
we
report
newly
conceived
blue-emitting
TADPL-producing
nanomaterials
featuring
InP
interfaced
1-
2-naphthoic
acid
(1-NA
2-NA)
ligands.
These
constitutional
isomers
feature
similar
energies
but
disparate
lifetimes,
translating
into
InP-based
processes
displaying
two
distinct
average
lifetime
ranges
upon
cooling
from
293
193
K.
The
time
constants
fall
between
4.4
59.2
μs
the
2-NA-decorated
while
further
expanding
84.2
733.2
corresponding
1-NA-ligated
materials,
representing
167-fold
window.
resulting
long-lived
excited
states
enabled
facile
bimolecular
sensitization
of
1O2
phosphorescence
near-IR
promoted
sensitized
triplet–triplet
annihilation
photochemistry
2,5-diphenyloxazole.
We
speculate
that
discovery
new
exhibiting
lies
on
horizon
myriad
can
be
readily
derivatized
using
numerous
classes
surface-anchoring
chromophores
yielding
precisely
regulated
photophysical
properties.
Nature Communications,
Journal Year:
2024,
Volume and Issue:
15(1)
Published: July 8, 2024
Solid-state
infrared-to-visible
photon
up-conversion
is
important
for
spectral-tailoring
applications.
However,
existing
systems
not
only
suffer
from
low
efficiencies
and
a
need
high
excitation
intensity,
but
also
exhibit
limited
selection
of
materials
complex
fabrication
processes.
Herein,
we
propose
sensitizer
with
bulk-heterojunction
structure,
comprising
both
an
energy
donor
acceptor,
triplet-triplet
annihilation
devices.
The
occurs
through
charge
separation
at
the
donor-acceptor
interface,
followed
by
formation
transfer
state
between
annihilator
following
spin
statistics.
ensures
efficient
generation
recombination.
Hence,
achieve
highly
solid-state
device
2.20%
efficiency
intensity
(10
mW
cm
