Advanced Energy Materials,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Nov. 26, 2024
Abstract
The
electron‐deficient
A
1
unit
in
A‐DA
D‐A
structured
acceptors
is
critical
for
optimizing
the
efficiency
of
organic
solar
cells
(OSCs).
Drawing
inspiration
from
high
performance
previously
reported
pyrido[2,3‐
b
]quinoxaline‐core
acceptors,
Py6,
an
isomer
Py1
designed
with
a
repositioned
pyridine
nitrogen
atom,
and
further
modified
it
by
chlorinating
Py6
to
create
Py7.
Theoretical
calculations
show
that
chlorine
incorporation
strengthens
intermolecular
non‐covalent
interactions
promotes
tighter
molecular
stacking,
as
confirmed
grazing‐incidence
wide‐angle
X‐ray
scattering.
Consequently,
D18/Py7
device
delivers
enhanced
fill
factor
short‐circuit
current
density,
compared
D18/Py1
D18/Py6
device.
Notably,
also
yields
higher
open‐circuit
voltage
0.871
V,
significantly
outperforming
(0.764
V)
(0.723
V),
due
low
nonradiative
energy
losses.
Further
studies
reveal
introducing
Cl
directs
hole
density
toward
central
pyrido[3,4‐
]quinoxaline
decreases
charge
transfer
state
ratio
D18/acceptor.
This
prompts
triplet‐to‐singlet
conversion
reduces
non‐radiative
recombination
Additionally,
using
mutual
donor–acceptor
dilution
strategy,
(D18:1wt.%
Py7)/(Py7:1wt.%
D18)
achieves
impressive
19.60%.
work
emphasizes
great
potential
Py‐series
demonstrates
effectively
Advanced Materials,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 28, 2025
Abstract
Simultaneously
mitigating
both
photovoltage
and
photocurrent
losses
is
crucial
for
organic
solar
cells
(OSCs)
to
approach
the
Shockley–Queisser
limit
of
ideal
efficiency.
Incorporating
a
narrower
bandgap
nonfullerene
acceptor
(NFA)
as
guest
component
into
host
donor:NFA
system
broadens
absorption
spectrum.
However,
this
can
also
increase
nonradiative
decay
rate
according
energy‐gap
law.
In
work,
ternary
OSCs
are
constructed
by
combining
narrow
AQx‐2F
(as
NFA)
with
lower
eC9
NFA),
significantly
enhancing
generation
without
compromising
photovoltage.
The
addition
acts
crystallization
inducer,
extending
period
increasing
ordered
packing
distance.
This
leads
suppressed
trap
states,
elevated
dielectric
constant,
prolonged
exciton
lifetime,
balanced
hole/electron
transport,
reduced
recombination
loss.
Consequently,
optimized
D18:AQx‐2F:eC9
achieve
champion
power
conversion
efficiency
(PCE)
20.6%
high
open‐circuit
voltage
0.937
V,
short‐circuit
current
density
27.2
mA
cm
−2
fill
factor
80.8%,
validated
an
independently
certified
PCE
20.0%,
establishing
new
benchmark
bulk
heterojunction
OSCs.
work
demonstrates
effective
method
simultaneously
mitigate
losses,
paving
way
high‐performance
Materials Chemistry Frontiers,
Journal Year:
2024,
Volume and Issue:
8(21), P. 3587 - 3595
Published: Jan. 1, 2024
Three
acceptors
with
different
aromatic
side
chains
were
synthesized
and
the
photovoltaic
performance
effects
of
steric
hindrances
studied.
BTP-1-iPr
better
matches
energy
level
PM6,
obtaining
higher
V
OC
,
FF
PCE
17.19%.
Communications Chemistry,
Journal Year:
2025,
Volume and Issue:
8(1)
Published: Jan. 9, 2025
Abstract
Various
photoactive
molecules
contain
motifs
built
on
aza-aromatic
heterocycles,
although
a
detailed
understanding
of
the
excited
state
photophysics
and
photochemistry
in
such
systems
is
not
fully
developed.
To
help
address
this
issue,
non-adiabatic
dynamics
operating
azanaphthalenes
under
hexane
solvation
was
studied
following
267
nm
excitation
using
ultrafast
transient
absorption
spectroscopy.
Specifically,
species
quinoline,
isoquinoline,
quinazoline,
quinoxaline,
1,6-naphthyridine,
1,8-naphthyridine
were
investigated,
providing
systematic
variation
relative
positioning
nitrogen
heteroatom
centres
within
bicyclic
aromatic
structure.
Our
results
indicate
considerable
differences
lifetimes,
propensity
for
intersystem
crossing
vs
internal
conversion
across
molecular
series.
The
overall
pattern
behaviour
can
be
explained
terms
potential
energy
barriers
spin-orbit
coupling
effects,
as
demonstrated
by
extensive
quantum
chemistry
calculations
undertaken
at
SCS-ADC(2)
level
theory.
fact
that
achieve
nuanced
agreement
with
experimental
data
full
set
six
exhibiting
subtle
variations
their
composition
provides
an
excellent
example
current
state-of-the-art
indicative
future
opportunities
rational
design
molecules.
Nature Communications,
Journal Year:
2025,
Volume and Issue:
16(1)
Published: Feb. 14, 2025
Fullerene
derivatives
are
widely
employed
as
efficient
electron-transporting
layers
(ETLs)
in
p-i-n
perovskite
photovoltaics
but
face
challenges
mitigating
interfacial
recombination
losses
and
ensuring
stable
film
morphology.
Non-fullerene
acceptors
(NFAs),
commonly
utilized
organic
photovoltaics,
present
a
promising
alternative
to
fullerene-based
ETLs.
Nevertheless,
the
suboptimal
performance
of
NFA-based
devices
underscores
need
for
molecular
engineering
tailor
their
properties.
Herein,
we
develop
two
Y-type
NFAs,
Y-Phen
Y-CE,
by
substituting
benzothiadiazole
core
Y6
with
higher-polarity
phenanthroline
crown
ether.
These
modifications
effectively
enhance
carrier
kinetics
(1)
promoting
ordered
assembly
on
surface
through
supramolecular
interactions,
thereby
optimizing
energetic
alignment,
(2)
improving
packing
facilitate
charge
transport.
Using
Y-CE
ETL,
device
achieves
certified
power
conversion
efficiency
(PCE)
25.59%.
Furthermore,
optimized
exhibits
less
than
10%
degradation
PCE
after
1440
hours
thermal
aging.
This
work
offers
valuable
insights
into
designing
ETLs
high-performance
photovoltaics.
The
solar
cells
based
non-fullerene
acceptor
layer
engineering.
Here,
authors
substitute
ether,
achieving
Advanced Materials,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 3, 2025
Abstract
The
development
of
organic
solar
cells
(OSCs)
with
high
efficiency
and
stability
is
highly
desirable
to
facilitate
its
commercial
applications.
Although
dimeric
acceptors
distinctive
advantages
have
been
widely
studied,
high‐performance
binary
OSCs
based
on
such
molecules
rarely
achieved.
In
this
work,
a
new
acceptor
(DY‐FL)
constructed
by
simultaneously
optimizing
the
linking
sites
units,
as
well
building
blocks.
Thanks
effective
molecular
design,
DY‐FL
provides
improved
stacking
for
fibrous
morphology
favorable
exciton/charge
dynamics.
Consequently,
DY‐FL‐based
render
superior
power
conversion
(PCE)
19.78%,
representing
record‐breaking
acceptors.
Importantly,
devices
display
significantly
enhanced
operational
under
external
stimuli
light
heat,
in
comparison
their
small
molecule
(Y‐F)‐based
counterpart.
These
findings
highlight
significance
blocks
modes,
providing
insight
into
design
strategy
state‐of‐the‐art
OSCs.
Advanced Energy Materials,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Nov. 14, 2024
Abstract
Molecular
stacking
behavior
exerts
a
significant
influence
on
the
blend
film
morphology
of
organic
solar
cells
(OSCs),
further
affecting
device
performance
and
stability.
Modulation
molecular
structure,
such
as
central
unit
end‐group,
can
profoundly
impact
this
process.
Herein,
four
quinoxaline
(Qx)‐fused‐core‐based
non‐fullerene
acceptors
(NFAs),
Qx‐N4F
Qx‐
o/m/p
‐N4F
are
synthesized
combining
π‐extended
end‐groups
optimized
units.
The
isomeric
fluorinated
units
lead
to
changes
in
local
dipole
moments
electrostatic
potential
distribution,
which
influences
pattern
photoelectronic
properties
NFAs.
Consequently,
binary
ternary
devices
based
PM6:Qx‐
p
achieve
superior
power
conversion
efficiencies
(PCE)
up
18.75%
19.48%,
respectively.
Grazing‐incidence
wide‐angle
X‐ray
scattering
(GIWAXS)
characterization
reveals
‐N4F's
stronger
crystallinity,
aggregation,
donor–acceptor
interactions,
separately
enhance
short‐circuit
current
density
(
J
SC
)
fill
factor
(FF)
through
higher
phase
purity
tighter
maintaining
more
interfaces.
Furthermore,
‐N4F‐based
demonstrate
exceptional
thermal
stability,
retaining
93.2%
initial
PCE
value
after
3000
h
heating
due
best
morphological
stability
with
most
stable
structure.
These
results
underscore
significance
synergistic
optimization
NFAs
conjugation
expansion
halogenation
substitution
for
obtaining
efficient
OSCs.
In
this
work,
three
alkoxy-substituted
quinoxaline
core-based
small-molecule
acceptors
(BQO-F,
BQDO-F,
and
BQDO-Cl)
are
developed
to
elucidate
the
impact
of
ethoxy
substituents
on
physicochemical
photoelectric
properties.
Comparative
analysis
reveals
that
dialkoxy-substituted
BQDO-F
has
a
more
planar
molecular
skeleton,
red-shifted
absorption
spectrum,
upshifted
energy
levels,
stronger
crystallinity,
reduced
energetic
disorder
compared
monoalkoxy-substituted
BQO-F.
Although
replacement
fluorine
atoms
with
chlorine
end-capped
units
leads
bathochromically
shifted
resulting
molecule
BQDO-Cl
shows
worse
π-π
packing
order
BQDO-F.
Benefiting
from
favorable
active
layer
morphology
improved
carrier
dynamics,
PBDB-T:BQDO-F-based
organic
solar
cell
achieves
much
higher
power
conversion
efficiency
(PCE)
16.41%
14.48%
obtained
in
BQO-F-based
device.
comparison
BQDO-F-based
device,
voltage
loss
BQDO-Cl-based
device
results
lower
PCE
15.89%.
The
clarify
effects
substitutions
efficient
cells.