Abstract
Nanoparticle
exsolution
has
emerged
as
a
versatile
method
to
functionalize
oxides
with
robust
metallic
nanoparticles
for
catalytic
and
energy
applications.
By
modifying
certain
external
parameters
during
thermal
reduction
(temperature,
time,
reducing
gas),
some
morphological
and/or
compositional
properties
of
the
exsolved
can
be
tuned.
Here,
it
is
shown
how
application
high
pressure
(<100
bar
H
2
)
enables
control
ternary
FeCoNi
alloyed
from
double
perovskite.
affects
lattice
expansion
nanoparticle
characteristics
(size,
population,
composition).
The
composition
could
controlled,
showing
reversal
expected
thermodynamic
trend
at
10
50
bar,
where
Fe
becomes
main
component
instead
Ni.
In
addition,
drastically
lowers
temperature
300
°C,
resulting
in
unprecedented
highly‐dispersed
small‐sized
similar
those
obtained
600
°C
bar.
mechanisms
behind
effects
on
are
discussed,
involving
kinetic,
surface
thermodynamics,
lattice‐strain
factors.
A
volcano‐like
extent
suggests
that
competing
pressure‐dependent
govern
process.
Pressure
emerges
new
design
tool
enabling
novel
nanocatalysts
surface‐functionalized
materials.
Abstract
Crystalline
perovskite
oxides
are
regarded
as
promising
electrocatalysts
for
water
electrolysis,
particularly
anodic
oxygen
evolution
reactions,
owing
to
their
low
cost
and
high
intrinsic
activity.
Perovskite
with
noncrystalline
or
amorphous
characteristics
also
exhibit
electrocatalytic
performance
toward
electrochemical
splitting.
In
this
review,
a
fundamental
understanding
of
the
advantages
crystalline,
noncrystalline,
is
presented.
Subsequently,
recent
progress
in
development
advanced
electrolysis
by
engineering
breaking
crystallinity
reviewed,
special
focus
on
underlying
structure–activity
relationships.
Finally,
remaining
challenges
unsolved
issues
presented,
an
outlook
briefly
proposed
future
exploration
next‐generation
water‐splitting
based
oxides.
Metal
nanocatalysts
supported
on
oxide
scaffolds
have
been
widely
used
in
energy
storage
and
conversion
reactions.
So
far,
the
main
research
is
still
focused
growth,
density,
size,
activity
enhancement
of
exsolved
nanoparticles
(NPs).
However,
lack
precise
regulation
type
composition
NPs
elements
under
reduction
conditions
has
restricted
architectural
development
situ
exsolution
systems.
Herein,
we
propose
a
strategy
to
attain
regulated
distribution
transition
metals
(Cu,
Ni,
Fe)
Sr2Fe1.2Ni0.2Cu0.2Mo0.4O6–δ
medium-entropy
perovskite
oxides
by
varying
oxygen
partial
pressure
(pO2)
gradient
mixture.
At
800
°C,
unitary
Cu,
binary
Cu–Ni,
ternary
Cu–Ni–Fe
are
as
pO2
decreases
from
high
low.
Combining
experimental
theoretical
simulations,
further
corroborate
that
solid
electrolysis
cells
with
alloy
clusters
at
CNF@SFO
interface
exhibit
superior
CO2
electrolytic
performance.
Our
results
provide
tailored
strategies
for
nanostructures
nanointerfaces
studying
metal
systems,
including
fuel
electrode
materials.
Nano-Micro Letters,
Год журнала:
2025,
Номер
17(1)
Опубликована: Фев. 8, 2025
Quasi-two-dimensional
(2D)
perovskite
embodies
characteristics
of
both
three-dimensional
(3D)
and
2D
perovskites,
achieving
the
superior
external
environment
stability
structure
perovskites
alongside
high
efficiency
3D
perovskites.
This
effect
is
realized
through
critical
structural
modifications
in
device
fabrication.
Typically,
have
an
octahedral
structure,
generally
ABX3,
where
organic
ammonium
cation
(A')
participates
forming
with
A'(n)
(n
=
1
or
2)
sandwiched
between
A(n-1)B(n)X(3n+1)
layers.
Depending
on
whether
A'
a
monovalent
divalent
cation,
are
classified
into
Ruddlesden-Popper
Dion-Jacobson
perovskite,
each
generating
different
structures.
Although
achieves
similar
effects,
they
incorporate
distinct
mechanisms
their
formation.
And
according
to
these
structures,
various
properties
appear,
additive
optimizing
methods
increase
also
exist
In
this
review,
scientific
understanding
engineering
perspectives
quasi-2D
investigated,
optimal
optimization
discussed
provide
insight
field.
Nano-Micro Letters,
Год журнала:
2025,
Номер
17(1)
Опубликована: Фев. 17, 2025
Abstract
Reversible
solid
oxide
cells
(RSOCs)
are
capable
of
converting
various
energy
resources,
between
electricity
and
chemical
fuels,
with
high
efficiency
flexibility,
making
them
suitable
for
grid
balancing
renewable
consumption.
However,
the
practical
application
RSOCs
is
still
limited
by
insufficient
activity
stability
electrodes
in
different
operating
modes.
Herein,
a
highly
efficient
symmetrical
electrode
composed
La
0.3
Sr
0.6
Ti
0.1
Co
0.2
Fe
0.7
O
3−
δ
(LSTCF)
nanofibers
situ
exsolved
3
7
nanoparticles
developed
boosting
performance
RSOCs.
The
reversible
phase
transition,
have
been
confirmed
combination
experimental
(e.g.,
transmission
electron
microscopy
X-ray
absorption
fine
structure)
computational
studies.
Electrolyte-supported
demonstrate
excellent
catalytic
stability,
achieving
peak
power
density
0.98
W
cm
−2
fuel
cell
mode
using
H
2
as
(or
0.53
CH
4
fuel)
current
1.09
A
at
1.4
V
CO
electrolysis
1.03
1.3
electrolysis)
800
°C
while
maintaining
durability
over
100
h.
Catalysis Today,
Год журнала:
2024,
Номер
437, С. 114787 - 114787
Опубликована: Май 8, 2024
Perovskite-type
oxides
have
gained
significant
attention
in
the
scientific
community
due
to
their
unique
properties
and
potential
applications.
Their
ability
exsolve
reducible
B-site
cations
(e.g.
Co,
Ni,
Cu)
combined
with
flexibility
regarding
A-site
composition
allows
for
tailoring
of
novel
catalytic
materials.
This
study
focuses
on
doped
perovskite-type
a
general
formula
Nd0.6Ca0.4Fe1-xCuxO3
Pr0.6Ca0.4Fe1-xCuxO3
(x
=
0.0,
0.03,
0.05,
0.10)
use
as
catalyst
Methanol
Steam
Reforming
via
exsolution
catalytically
active
Cu
nanoparticles.
The
atomic
electronic
structure,
morphology,
behaviour
these
materials
were
investigated
experimentally
density
functional
theory,
specific
emphasis
impact
doping
varying
content
well
choice
element.
Both
parameters
influenced
crystal
surface
area,
morphology
was
observed
using
in-situ
XRD
at
DESY
beamline
P02.1
PETRA
III,
nanoparticles
forming
after
reductive
treatments
host
oxide
surface.
quantity
size
found
be
adjustable
by
selecting
ion,
B-site,
reducing
agent.
Materials
higher
exhibited
facilitated
exsolution.
Furthermore,
promoted
Nd
element
compared
Pr.
In
conclusion,
controlled
introduces
Cu-doped
promising
candidates
developing
systems.
findings
underscore
importance
fine-tuning
(A-site
element,
amount
dopant)
achieve
tailored
nanoparticles,
which
is
crucial
rational
material
design.
By
leveraging
this
knowledge,
catalysts
finely
tuned
can
created
applications
operational
environments.
Journal of the American Ceramic Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 9, 2025
Abstract
In
this
work,
exsolution
is
achieved
from
both
the
A‐site
and
B‐site
of
(BaGd
0.8
La
0.2
)
1‐
x
Ag
Co
2
O
6‐
δ
(BaLa)
CoFeO
(
=
0.04,
0.1,
0.2)
perovskites
prepared
via
solid‐state
sintering.
Through
synchrotron
radiation
powder
X‐ray
diffraction
absorption
spectroscopy
techniques,
chemical
composition
nanoparticles
was
determined
to
constitute
CoO.
Microstructural
studies
were
done
using
scanning
electron
microscopy
with
varying
sizes
shapes
present
for
respective
annealing
atmospheres
temperatures.
By
applying
a
numerical
model
experimental
data,
it
also
established
that
changes
in
enthalpy
oxygen
vacancy
formation
decrease
an
increase
silver
dopant.
From
thermogravimetric
measurements,
single
0.95
0.10
perovskite
had
relatively
higher
water
uptake
than
layered
perovskite.
The
total
electrical
conductivity
dry
wet
conditions
decreased
temperature
range
300–800°C
perovskites.
results
obtained
relaxation
measurements
exhibit
increased
reduction
reaction
activity
6‐δ
nanoparticles.
