Advanced Sustainable Systems,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 27, 2024
Abstract
Recent
progress
in
the
design
and
preparation
of
dense
ion‐conducting
membranes,
to
improve
redox
flow
batteries
(RFBs)
performance
are
critically
examined.
The
ideal
membrane
has
balance
a
high
ionic
conductivity,
low
crossover
ion/redox‐active
species,
coulombic
voltage
efficiencies.
Several
ion
exchange
membranes
analyzed,
with
focus
on
proton
(PEMs),
that
most
mature
technology
RFBs,
led
by
gold
standard
Nafion.
Key
developments
include
synthesis
tailored
(co)polymers,
post‐functionalization
commercially
available
ones,
formation
techniques
like
electrospinning,
polymer
blending,
additions
organic
inorganic
fillers,
surface
modification.
Dense,
asymmetric
composite
reported
discussed.
effects
properties
macromolecular
parameters
(polymer
backbone,
type
length
side
chains,
acidity
ion‐exchanging
group)
highlighted.
Correlations
between
chemical
structure,
discussed,
targeting
trade‐off
selectivity
overall
RFB
cell.
Although
significant
steps
forward
development
were
made,
improvements
electrochemical
long‐term
stability,
while
reducing
costs,
still
challenging
necessary
large‐scale
application
RFBs.
National Science Review,
Год журнала:
2024,
Номер
12(2)
Опубликована: Ноя. 29, 2024
ABSTRACT
Ion
exchange
membranes
(IEMs)
enable
fast
and
selective
ion
transport
the
partition
of
electrode
reactions,
playing
an
important
role
in
fields
precise
separation,
renewable
energy
storage
conversion,
clean
production.
Traditional
IEMs
form
channels
at
nanometer-scale
via
assembly
flexible
polymeric
chains,
which
are
trapped
permeability/conductivity
selectivity
trade-off
dilemma
due
to
a
high
swelling
propensity.
New-generation
have
shown
great
potential
break
this
intrinsic
limitation
by
using
microporous
framework
for
under
confinement
regime.
In
Review,
we
first
describe
fundamental
principles
charged
from
nanometer
sub-nanometer
scale.
Then,
focus
on
construction
new-generation
highlight
effects
sub-2-nm
sub-1-nm
further
ultra-micropores.
The
enhanced
properties
brought
intense
size
sieving
channel
interaction
elucidated,
corresponding
applications
including
lithium
flow
battery,
water
electrolysis,
ammonia
synthesis
introduced.
Finally,
prospect
future
development
with
respect
intricate
microstructure
observation,
in-situ
visualization,
large-scale
membrane
fabrication.
Advanced Energy Materials,
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 14, 2025
Abstract
Non‐fluorinated
polymer
membranes
offer
a
commercially
feasible
solution
for
redox
flow
batteries
(RFBs),
yet
their
practical
applications
have
been
hampered
by
inherent
challenges
such
as
chemical
instability
and
low
ionic
conductivity.
In
this
study,
the
development
of
series
ether‐bond‐free
poly(aryl
piperidine)
that
address
these
limitations
introducing
enhanced
disorder
in
chain
packing
through
supramolecular
interactions
with
organic
acids,
is
presented.
These
effectively
disrupt
densely
packed
chains,
transforming
proton‐inaccessible
crystalline
regions
into
accessible
amorphous
ones.
By
eliminating
chemically
unstable
aryl
ether
bonds
avoiding
additional
modifications,
exhibit
remarkable
long‐term
stability.
The
presence
abundant
interchain
gaps
further
facilitates
rapid
proton‐selective
transport.
As
result,
engineered
demonstrate
sustained
performance
vanadium
RFBs,
maintaining
stable
operation
over
1000
charge/discharge
cycles,
achieving
an
impressive
energy
efficiency
80%
at
high
current
density
280
mA
cm
−
2
.
combination
experimental
data
theoretical
modeling
suggests
membrane's
outstanding
arises
from
interconnected
widely
distributed
gaps,
which
pore‐limiting
diameter
≈8
Å.
findings
robust
design
strategy
developing
stable,
high‐performance
non‐fluorinated
RFBs
related
conversion
devices.
Abstract
The
swift
advancement
of
monovalent
anion
perm‐selective
membranes
(MAPMs)
presents
a
promising
and
sustainable
approach
for
separation.
However,
their
progress
remains
predominantly
based
on
microphase‐separated
characterized
by
wide,
swelling
ion‐selective
channels.
In
this
study,
the
rigidity
flexibility
coupled
concept
was
employed
to
engineer
rigidly
confined
channels
within
MAPMs
facilitate
rigid
segments
self‐assemble
into
micropores
(<0.8
nm),
with
dimensions
precisely
modulated
flexible
segments.
Under
electrodialysis
conditions,
these
demonstrate
an
order‐of‐magnitude
improvement
in
selectivity
compared
Neosepta®
ACS
commercial
(special
separation),
slight
increase
permeation
flux
anions.
simulation
results
confirm
that
difference
confinement
various
anions,
driven
electrostatic
interactions
micropores,
is
responsible
exceptional
monovalent/bivalent
selectivity.
Overall,
study
provides
alternative
strategy
construct
efficient
Macromolecular Rapid Communications,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 29, 2025
Abstract
The
high
conductivity
of
anion
exchange
membrane
(AEM)
remains
a
great
challenge
in
achieving
high‐performance
vanadium
flow
batteries.
In
this
work,
is
achieved
by
designing
series
microporous
crosslinked
quaternary
ammonium
membranes
(QDTTB‐Xs),
which
synthesized
situ
reacting
iodomethane
with
novel
Tröger
base
(DTTB‐Xs)
that
prepared
condensation
2,
6
(7)‐diamino‐triptycene
and
(7)‐13‐triamino‐triptycene
through
crosslinking.
Compared
linear
QDTTB‐0,
the
QDTTB‐X
showed
higher
conductivity.
QDTTB‐35
displays
both
coulombic
efficiency
voltage
efficiency,
80%
energy
realized
at
200
mA
cm
−2
.
Outperforming
N117
other
reported
membranes.
This
due
to
increased
triamino‐triptycene
molar
ratio
resulting
N
+
concentration
improved
micropores
concentration.
Moreover,
positively
charged
groups
combined
low
swelling
also
help
restricting
ions
permeation.
These
results
give
perspectives
AEMs
for
VRFB
applications.
