ACS Nano,
Год журнала:
2023,
Номер
18(1), С. 560 - 570
Опубликована: Дек. 18, 2023
Induced
polarization
response
and
integrated
magnetic
resonance
show
prosperous
advantages
in
boosting
electromagnetic
wave
absorption
but
still
face
huge
challenges
revealing
the
intrinsic
mechanism.
In
this
work,
we
propose
a
self-confined
strategy
to
construct
hierarchical
Fe-Co@TiO2
microrods
with
numerous
incoherent
heterointerfaces
gradient
domains.
The
results
demonstrate
that
use
of
polyvinylpyrrolidone
(PVP)
coating
is
crucial
for
subsequent
deposition
Co-zeolitic
imidazolate
frameworks
(ZIF-67),
distance
ordered
arranged
metal
ions
manipulates
size
domains,
pyrolysis
PVP
layers
restricts
eutectic
process
Fe-Co
alloys
some
extent.
As
result,
these
introduced
lattice
defects,
oxygen
vacancies,
inevitably
generate
strong
response,
regulated
domains
realize
resonance,
including
macroscopic
coupling,
long-range
diffraction,
nanoscale
bridge
connection,
both
mechanisms
dissipating
energy
are
quantitatively
clarified
by
Lorentz
off-axis
electron
holography.
Owing
cooperative
merits,
absorbents
exhibit
enhanced
intensity
bandwidth.
This
study
inspires
us
develop
generalized
manipulating
theory
provides
versatile
methodology
clarifying
loss
Advanced Functional Materials,
Год журнала:
2022,
Номер
33(1)
Опубликована: Окт. 27, 2022
Abstract
High‐entropy
(HE)
oxides
have
become
increasingly
popular
as
electromagnetic
wave‐absorbing
materials
owing
to
their
customizable
structure
and
unique
HE
effects.
However,
the
weak
loss
property
of
single‐phase
ceramics
approaches
implemented
improve
them
based
on
semi‐empirical
rules
severely
limit
development.
Herein,
two
biphasic
are
prepared
by
simple
sintering
realize
accurate
regulation
crystal
phases
structural
defects.
It
is
verified
that
effects
cause
various
defects
beneficial
for
microwave
dissipation
within
complex‐phase
ceramics.
In
spinel/perovskite
oxides,
around
interface
spinel
(111)
perovskite
(110)
planes,
notable
stress
concentrations
lattice
distortions
directly
observed,
inducing
numerous
point
stacking
faults.
Interestingly,
besides
existing
heterogeneous
rock
salt
(220)/spinel
(220)
plane
defects,
salt/spinel
enabled
synergistic
via
precise
components’
phase.
Driven
multi‐phases
in
complexes,
intense
polarization
evidently
found,
confirmed
first‐principles
calculations.
Accordingly,
demonstrate
excellent
absorption
performance,
minimal
reflection
−54.5
dB
achieved.
Therefore,
this
study
provides
valuable
guidelines
design
absorbers
using
oxides.
Nano-Micro Letters,
Год журнала:
2022,
Номер
14(1)
Опубликована: Авг. 20, 2022
Developing
ultrabroad
radar-infrared
compatible
stealth
materials
has
turned
into
a
research
hotspot,
which
is
still
problem
to
be
solved.
Herein,
the
copper
sulfide
wrapped
by
reduced
graphene
oxide
obtain
three-dimensional
(3D)
porous
network
composite
aerogels
(CuS@rGO)
were
synthesized
via
thermal
reduction
ways
(hydrothermal,
ascorbic
acid
reduction)
and
freeze-drying
strategy.
It
was
discovered
that
phase
components
(rGO
CuS
phases)
micro/nano
structure
(microporous
nanosheet)
well-modified
modulating
additive
amounts
of
changing
ways,
resulted
in
variation
pore
structure,
defects,
complex
permittivity,
microwave
absorption,
radar
cross
section
(RCS)
value
infrared
(IR)
emissivity.
Notably,
obtained
CuS@rGO
with
single
dielectric
loss
type
can
achieve
an
bandwidth
8.44
GHz
at
2.8
mm
low
filler
content
6
wt%
hydrothermal
method.
Besides,
aerogel
realizes
minimum
reflection
(RLmin)
-
60.3
dB
lower
2
wt%.
The
RCS
reach
53.3
m2,
effectively
reduces
probability
target
being
detected
detector.
Furthermore,
laminated
architecture
multicomponent
endowed
insulation
IR
versatility.
Thus,
this
work
offers
facile
method
design
develop
rGO-based
absorbers
radar-IR
stealth.
Advanced Functional Materials,
Год журнала:
2022,
Номер
32(33)
Опубликована: Июнь 1, 2022
Abstract
Hierarchical
engineering
of
suitable
dielectric‐magnetic
multicomponents
shows
good
performance
for
microwave
absorbers,
but
still
face
bottlenecks.
Herein,
hierarchical
double‐shelled
nanotubes
(DSNTs),
in
which
the
inner
magnetic
tubular
subunits
are
assembled
by
magnetic‐heteroatomic
components
through
cation‐exchange
reactions,
and
outer
dielectric
MnO
2
nanosheets
strengthen
synergistic
interactions
between
confined
heterogeneous
interfaces
ingeniously
designed
constructed.
Hetero‐interfaces
induced
polarization
is
proposed
to
investigate
interfacial
relaxation
mechanism,
loss,
closely
related
micrometer‐scale
units,
mainly
clarified
interaction
composed
coupling
diffraction;
both
them
clearly
confirmed
Lorentz
off‐axis
electron
holography.
The
obtained
DSNTs
demonstrate
efficient
absorption
with
an
optimal
reflection
loss
−54.7
dB
qualified
bandwidth
9.5
GHz
owing
desirable
interfaces,
multiple
heteroatomic
hollow
microstructures.
This
strategy
inspires
a
generalized
methodology
configurations
multishells,
combination
hetero‐interfaces
microscale
broadens
mechanism
topography–performance
relationship
materials.
Nano-Micro Letters,
Год журнала:
2022,
Номер
14(1)
Опубликована: Фев. 21, 2022
The
development
of
multifunctional
and
efficient
electromagnetic
wave
absorbing
materials
is
a
challenging
research
hotspot.
Here,
the
magnetized
Ni
flower/MXene
hybrids
are
successfully
assembled
on
surface
melamine
foam
(MF)
through
electrostatic
self-assembly
dip-coating
adsorption
process,
realizing
integration
microwave
absorption,
infrared
stealth,
flame
retardant.
Remarkably,
Ni/MXene-MF
achieves
minimum
reflection
loss
(RLmin)
-
62.7
dB
with
corresponding
effective
absorption
bandwidth
(EAB)
6.24
GHz
at
2
mm
an
EAB
6.88
1.8
mm.
Strong
attributed
to
three-dimensional
magnetic/conductive
networks,
which
provided
excellent
impedance
matching,
dielectric
loss,
magnetic
interface
polarization,
multiple
attenuations.
In
addition,
endows
low
density,
heat
insulation,
flame-retardant
functions.
This
work
new
strategy
for
design
materials.
Nano-Micro Letters,
Год журнала:
2022,
Номер
14(1)
Опубликована: Авг. 20, 2022
Rational
designing
of
one-dimensional
(1D)
magnetic
alloy
to
facilitate
electromagnetic
(EM)
wave
attenuation
capability
in
low-frequency
(2-6
GHz)
microwave
absorption
field
is
highly
desired
but
remains
a
significant
challenge.
In
this
study,
composite
EM
absorber
made
FeCoNi
medium-entropy
embedded
1D
carbon
matrix
framework
rationally
designed
through
an
improved
electrospinning
method.
The
1D-shaped
demonstrates
the
high-density
and
continuous
network
using
off-axis
electronic
holography
technique,
indicating
excellent
loss
ability
under
external
field.
Then,
in-depth
analysis
shows
that
many
factors,
including
anisotropy
intrinsic
physical
features
alloy,
primarily
contribute
enhanced
performance.
Therefore,
fabricated
increasing
effective
band
1.3
GHz
at
ultrathin
thickness
2
mm.
Thus,
study
opens
up
new
method
for
design
preparation
high-performance
absorbers.
Advanced Functional Materials,
Год журнала:
2023,
Номер
33(16)
Опубликована: Фев. 7, 2023
Abstract
The
rational
design
of
magnetic
composites
has
great
potential
for
electromagnetic
(EM)
absorption,
particularly
in
the
low‐frequency
range
2–8
GHz.
However,
scalable
synthesis
such
absorbers
with
both
high
content
and
good
dispersity
remains
challenging.
In
this
study,
a
confined
diffusion
strategy
is
proposed
to
fabricate
functional
magnetic‐carbon
hollow
microspheres.
Driven
by
ferromagnetic
enhanced
Kirkendall
effect,
situ
alloying
FeCo
nanoparticles
tightly
carbon
shells,
effectively
inhibiting
agglomeration.
Moreover,
core–shell
FeCo–carbon
nano‐units
further
assemble
into
dispersive
microscale
Janus
bulges
on
inner
outer
surfaces
microsphere.
optimized
FeCo@C
microspheres
exhibit
excellent
EM
wave
absorption
performance:
minimum
reflection
loss
(
RL
min
)
−35.9
dB,
bandwidth
covers
almost
entire
C‐band.
Systematic
investigation
reveals
that
large
size
integration,
high–density
units,
strong
coupling
are
essential
enhancing
dissipation
waves.
This
study
provides
novel
fabricating
advanced
significant
inspiration
investigating
attenuation
mechanism
at
low
frequency.
Nano-Micro Letters,
Год журнала:
2022,
Номер
14(1)
Опубликована: Апрель 19, 2022
Metal-organic
frameworks
(MOFs)
are
used
to
directly
initiate
the
gelation
of
graphene
oxide
(GO),
producing
MOF/rGO
aerogels.
The
ultralight
magnetic
and
dielectric
aerogels
show
remarkable
microwave
absorption
performance
with
ultralow
filling
contents.
development
a
convenient
methodology
for
synthesizing
hierarchically
porous
comprising
metal-organic
(GO)
building
blocks
that
exhibit
an
density
uniformly
distributed
MOFs
on
GO
sheets
is
important
various
applications.
Herein,
we
report
facile
route
MOF/reduced
(rGO)
based
GO,
which
initiated
using
MOF
crystals.
Free
metal
ions
exposed
surface
MIL-88A
nanorods
act
as
linkers
bind
nanosheets
three-dimensional
network
via
metal-oxygen
covalent
or
electrostatic
interactions.
MOF/rGO-derived
Fe3O4@C/rGO
Ni-doped
notable
(MA)
performance,
simultaneously
achieving
strong
broad
bandwidth
at
low
thickness
2.5
(-
58.1
dB
6.48
GHz)
2.8
mm
46.2
7.92
contents
0.7
0.6
wt%,
respectively.
attenuation
ability
prepared
further
confirmed
radar
cross-sectional
simulation,
attributed
synergistic
effects
their
structures
heterointerface
engineering.
This
work
provides
effective
pathway
fabricating
hybrid
offers
MA.
