ACS Energy Letters,
Journal Year:
2023,
Volume and Issue:
8(6), P. 2488 - 2495
Published: May 4, 2023
A
new
A-DA′D-A
structured
narrow
bandgap
small
molecular
acceptor
(SMA)
Se46
was
designed
and
synthesized
by
using
benzoselenadiazole
as
the
A′
unit
branched
2-butyloctyl
upper
side
chains
in
its
DA′D
central
fused
ring.
It
found
that
shows
red-shifted
absorption
compared
to
of
L8-BO
with
a
benzothiadiazole
an
up-shifted
lowest
unoccupied
orbital
energy
level
Y6
linear
n-C11H23
chains.
The
organic
solar
cells
(OSCs)
based
on
PM6:Se46
demonstrate
high
power
conversion
efficiency
over
18%
increased
short
circuit
current
density
L8-BO-based
devices
higher
open
voltage
than
Y6-based
devices.
results
indicate
synergetic
modification
selenium
substitution
alkyl
chain
is
effective
strategy
further
promote
photovoltaic
performance
for
type
acceptors.
Advanced Functional Materials,
Journal Year:
2022,
Volume and Issue:
32(35)
Published: July 5, 2022
Abstract
Symmetric
conjugated
molecules
can
be
broken
through
suitable
synthetic
strategies
to
construct
novel
asymmetric
molecules,
which
largely
broaden
the
material
library.
In
field
of
organic
solar
cells,
fused‐ring
electron
acceptors
(FREAs)
with
A‐DA'D‐A
type
backbone
structure
have
attracted
much
attention
and
enabled
power
conversion
efficiencies
(PCE)
exceeding
18%.
Among
them,
Y6
is
one
most
classic
FREAs
that
derive
many
symmetric
exhibit
unique
optoelectronic
properties.
Thus,
in
this
review,
focus
on
recent
progress
Y6‐derived
containing
a
dipyrrolobenzothiadiazole
segment,
classified
as
following
three
categories:
end
group,
central
core
side
chain.
The
relationship
molecular
structure,
properties,
device
performance
discussed
detail.
Finally,
future
design
directions
challenges
faced
by
kind
photovoltaic
materials
are
given.
Nature Communications,
Journal Year:
2023,
Volume and Issue:
14(1)
Published: Oct. 31, 2023
High-efficiency
organic
solar
cells
are
often
achieved
using
toxic
halogenated
solvents
and
additives
that
constrained
in
industry.
Therefore,
it
is
important
to
develop
materials
or
processing
methods
enabled
highly
efficient
processed
by
halogen
free
solvents.
In
this
paper,
we
report
an
innovative
method
named
auxiliary
sequential
deposition
enables
19%-efficiency
Our
different
from
the
conventional
blend
casting
involves
additional
of
dithieno[3,2-b:2',3'-d]thiophene
between
depositions
donor
(D18-Cl)
acceptor
(L8-BO)
layers.
The
dramatic
performance
enhancement
15%
over
18%
compared
methods.
Furthermore,
incorporating
a
branched-chain-engineered
called
L8-BO-X,
device
can
be
boosted
19%
due
increased
intermolecular
packing,
representing
top-tier
values
for
green-solvent
cells.
Comprehensive
morphological
time-resolved
characterizations
reveal
superior
morphology
through
promotes
charge
generation
while
simultaneously
suppressing
recombination.
This
research
underscores
potential
fabricating
environmentally
friendly
Aggregate,
Journal Year:
2022,
Volume and Issue:
3(6)
Published: Oct. 13, 2022
Abstract
The
power
conversion
efficiencies
(PCEs)
of
organic
solar
cells
(OSCs)
have
improved
considerably
in
recent
years
with
the
development
fused‐ring
electron
acceptors
(FREAs).
Currently,
FREAs‐based
OSCs
achieved
high
PCEs
over
19%
single‐junction
OSCs.
Whereas
relatively
synthetic
complexity
and
low
yield
FREAs
typically
result
production
costs,
hindering
commercial
application
In
contrast,
noncovalently
(NFREAs)
can
compensate
for
shortcomings
facilitate
large‐scale
industrial
by
virtue
simple
structure,
facile
synthesis,
yield,
cost,
reasonable
efficiency.
At
present,
based
on
NFREAs
exceeded
15%
are
expected
to
reach
comparable
efficiency
as
Here,
advances
this
review
provide
insight
into
improving
performance
particular,
paper
focuses
effect
chemical
structures
molecule
conformation,
aggregation,
packing
mode.
Various
molecular
design
strategies,
such
core,
side‐chain,
terminal
group
engineering,
presented.
addition,
some
novel
polymer
all‐polymer
also
introduced.
end,
provides
an
outlook
developing
efficient,
stable,
low‐cost
achieving
applications.
Angewandte Chemie International Edition,
Journal Year:
2022,
Volume and Issue:
61(46)
Published: Sept. 2, 2022
Herein,
we
synthesized
new
hetero-halogenated
end
groups
with
well-determined
fluorinated
and
chlorinated
substitutions
(o-FCl-IC
FClF-IC),
regioisomer-free
small
molecular
acceptors
(SMAs)
Y-Cl,
Y-FCl,
Y-FClF
distinct
terminals,
respectively.
The
single-crystal
structures
theoretical
calculations
indicate
that
exhibits
more
compact
three-dimensional
network
packing
significant
π-π
electronic
coupling
compared
to
Y-FCl.
From
Y-Cl
Y-FCl
Y-FClF,
the
neat
films
exhibit
a
narrower
optical
band
gap
gradually
enhanced
electron
mobility
crystallinity.
PM6
:
blend
film
strongest
crystallinity
preferential
face-on
packing,
desirable
fibrous
morphology
suitable
phase
segregation,
highest
balanced
charge
mobilities
among
three
films.
Overall,
organic
solar
cells
(OSCs)
deliver
remarkable
efficiency
of
17.65
%,
outperforming
which
is
best
PCE
for
reported
hetero-halogens-based
SMAs
in
binary
OSCs.
Our
results
demonstrate
difluoro-monochloro
hetero-terminal
superior
regio-regular
unit
enhancing
intermolecular
crystal
photovoltaic
performance
SMAs.
Nature Communications,
Journal Year:
2022,
Volume and Issue:
13(1)
Published: Oct. 8, 2022
Power
conversion
efficiency
and
long-term
stability
are
two
critical
metrics
for
evaluating
the
commercial
potential
of
organic
photovoltaics.
Although
field
has
witnessed
a
rapid
progress
towards
19%,
intrinsic
trade-off
between
is
still
challenging
issue
bulk-heterojunction
cells
due
to
very
delicate
crystallization
dynamics
species.
Herein,
we
developed
class
non-fullerene
acceptors
with
varied
side
groups
as
an
alternative
aliphatic
chains.
Among
them,
conjugated
show
larger
side-group
torsion
more
twisted
backbone,
however,
they
can
deliver
high
18.3%
in
xylene-processed
cells,
which
among
highest
values
reported
non-halogenated
solvent
processed
cells.
Meanwhile,
decent
thermal/photo
realized
these
containing
groups.
Through
investigation
geometry-performance-stability
relationship,
highlight
importance
steric
hinderance
achieving
combined
high-performance,
stable,
eco-friendly
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(30)
Published: May 26, 2023
Abstract
The
central
core
in
A‐DA
1
D‐A‐type
small‐molecule
acceptor
(SMAs)
plays
an
important
role
determining
the
efficiency
of
organic
solar
cells
(OSCs),
while
principles
governing
efficient
design
SMAs
remain
elusive.
Herein,
we
developed
a
series
with
pyrido[2,3‐
b
]quinoxaline
(PyQx)
as
new
electron‐deficient
unit
by
combining
cascade‐chlorination
strategy,
namely
Py1,
Py2,
Py3,
Py4
and
Py5.
introduction
chlorine
atoms
reduces
intramolecular
charge
transfer
effects
but
elevates
LUMO
values.
Density
functional
theory
(DFT)
reveals
that
Py2
ortho
substituted
PyQx
Py5
two
yield
larger
dipole
moments
smaller
π⋅⋅⋅π
stacking
distances,
compared
other
three
acceptors.
Moreover,
shows
strongest
light
absorption
capability
induced
extended
orbit
overlap
lengths
more
packing
structures
dimers.
These
features
endow
best
device
performance
due
to
better
molecular
aggregation
behaviors,
suitable
domain
sizes
exciton
dissociation
recombination.
This
study
highlights
significance
incorporating
large
moments,
small
distances
dimers
into
development
high‐performance
SMAs,
providing
insight
for
OSCs.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(10)
Published: Jan. 2, 2023
Side-chain
tailoring
is
a
promising
method
to
optimize
the
performance
of
organic
solar
cells
(OSCs).
However,
asymmetric
alkyl
chain-based
small
molecular
acceptors
(SMAs)
are
still
difficult
afford.
Herein,
we
adopted
novel
n-nonyl/undecyl
substitution
strategy
and
synthesized
two
A-D1
A'D2
-A
double
isomeric
SMAs
with
selenophene-based
central
core
for
OSCs.
Crystallographic
analysis
indicates
that
AYT9Se11-Cl
forms
more
compact
order
intermolecular
packing
compared
AYT11Se9-Cl,
which
contributed
higher
electron
mobility
in
neat
film.
Moreover,
PM6
:
blend
film
shows
better
morphology
appropriate
phase
separation
distinct
face-on
orientation
than
AYT11Se9-Cl.
The
OSCs
obtain
superior
PCE
18.12
%
AYT11Se9-Cl
(17.52
%),
best
efficiency
selenium-incorporated
binary
BHJ
Our
findings
elucidate
chains
precisely
modulates
crystal
enhances
photovoltaic
selenophene-incorporated
SMAs.
Energy & Environmental Science,
Journal Year:
2023,
Volume and Issue:
16(7), P. 2732 - 2758
Published: Jan. 1, 2023
This
review
summarizes
the
side-chain
engineering
of
nonfullerene
small-molecule
acceptors
(SMAs)
in
field
organic
solar
cells,
discusses
key
structure–property
relationships
depth
and
future
directions
engineering.