Journal of Advanced Ceramics,
Год журнала:
2023,
Номер
12(10), С. 1902 - 1918
Опубликована: Авг. 17, 2023
High-entropy
MXenes,
as
a
new
emerging
class
of
materials,
possess
diverse
compositions,
unexpected
physicochemical
characteristics
and
great
potentials
for
electromagnetic
(EM)
wave
absorption.
Herein,
two
single-to-few-layer
high-entropy
(Mo0.25Cr0.25Ti0.25V0.25)3C2Tx
(Mo0.2Cr0.2Nb0.2Ti0.2V0.2)4C3Tx,
were
synthesized
the
first
time.
During
exfoliation
delamination
processes,
structural,
morphological
compositional
evolutions
analyzed,
verifying
successful
formation
two-dimensional
MXene
nanosheets.
Investigations
indicate
that
with
filling
content
only
35
wt%,
powders
filled
composites
exhibit
high-efficiency
EM
absorption
performances.
The
f-(Mo0.25Cr0.25Ti0.25V0.25)3C2Tx
possesses
minimum
reflection
loss
(RLmin)
-45.0
dB
matching
thickness
1.52
mm
maximum
effective
bandwidth
(EAB)
5.6
GHz
at
1.65
thickness.
Also,
f-(Mo0.2Cr0.2Nb0.2Ti0.2V0.2)4C3Tx
can
attain
RLmin
-52.8
1.58
an
optimum
EAB
value
3.6
1.50
mm.
satisfactory
efficiency
bandwidth,
thin
low
prove
lightweight
advantage
application
potential
MXenes
in
In
this
work,
strategy
is
applied
to
tune
performances
MXenes.
Furthermore,
engineering
expected
provide
control
tunability
many
other
properties,
such
electrochemical,
catalytic,
mechanical
behaviors.
Nano-Micro Letters,
Год журнала:
2023,
Номер
15(1)
Опубликована: Июль 10, 2023
Wearable
devices
with
efficient
thermal
management
and
electromagnetic
interference
(EMI)
shielding
are
highly
desirable
for
improving
human
comfort
safety.
Herein,
a
multifunctional
wearable
carbon
fibers
(CF)
@
polyaniline
(PANI)
/
silver
nanowires
(Ag
NWs)
composites
"branch-trunk"
interlocked
micro/nanostructure
were
achieved
through
"three-in-one"
multi-scale
design.
The
reasonable
assembly
of
the
three
kinds
one-dimensional
(1D)
materials
can
fully
exert
their
excellent
properties
i.e.,
superior
flexibility
CF,
robustness
PANI,
splendid
conductivity
AgNWs.
Consequently,
constructed
flexible
composite
demonstrates
enhanced
mechanical
tensile
stress
1.2
MPa,
which
was
almost
6
times
that
original
material.
This
is
mainly
attributed
to
fact
PNAI
(branch)
firmly
attached
CF
(trunk)
polydopamine
(PDA),
forming
robust
structure.
Meanwhile,
possesses
insulation
heat
preservation
capacity
owing
synergistically
low
emissivity.
More
importantly,
conductive
path
established
by
1D
greatly
improved
its
EMI
property
Joule
heating
performance
at
applied
voltage.
work
paves
way
rational
utilization
intrinsic
materials,
as
well
provides
promising
strategy
designing
protection
energy
devices.
ACS Nano,
Год журнала:
2023,
Номер
17(20), С. 20525 - 20536
Опубликована: Окт. 10, 2023
The
emergence
of
green
flexible
aerogel
electronics
based
on
natural
materials
is
expected
to
solve
part
the
global
environmental
and
energy
crisis.
However,
it
still
challenging
achieve
large-scale
production
multifunctional
stable
applications
biomass
fiber
(BFA)
materials.
Herein,
we
exploit
interfacial
bridging
between
flower-type
titanium
dioxide
nanoarray
(FTNA)
substrates
modulate
electronic
structure
loss
mechanism
properties.
Specifically,
fibrous
substrate
with
wrinkled
features
induces
lattice
strain
in
titania
through
precise
bridging,
effectively
improving
intrinsic
properties
BFA
This
regulation
strategy
also
confirmed
by
X-ray
absorption
fine
spectroscopy
(XAS).
More
importantly,
construction
products
for
different
macroscopic
simple
processing
methods
will
facilitate
transition
from
electronics.
Therefore,
as-prepared
blanket-type
(TCBFA)
has
good
mechanical
properties,
electromagnetic
protection
thermal
stealth
high-temperature
flame
retardancy,
UV
resistance.
Meanwhile,
membrane-type
(TCBFAM)
wearable
device
exhibits
superior
flexibility,
efficient
Joule
heating
performance,
a
smart
response.
provides
another
concept
design
innovation
fiber-integrated
aerogels.
Advanced Functional Materials,
Год журнала:
2024,
Номер
34(44)
Опубликована: Май 21, 2024
Abstract
Anion
defect
engineering
is
proven
to
be
an
efficient
approach
reconstruct
the
electronic
configuration
of
carbon‐based
magnetoelectric
materials
for
targeted
modulation
electromagnetic
(EM)
performance.
However,
traditional
mono‐anionic
doping
suffers
from
low
concentration
and
lacks
diverse
polarization
mechanisms.
In
this
work,
multi‐anions
(N/S/F)
stepwise‐doped
carbon/Fe
3
C
composites
are
elaborately
constructed,
wherein
predesigned
N
defects
serve
as
activated
sites
anomalously
adopting
S
anions
(Step
I)
subsequent
F
II)
in
non‐marginal
areas
carbon
layer.
It
found
that
prefers
replace
pyrrolic
while
tends
form
dangling
bonds
with
site
adjacent
pyridinic
N.
Intriguingly,
besides
inherent
polarized
resonance
at
≈15
GHz,
customized
induce
new
resonances
≈10
GHz
≈15+
respectively.
Under
a
typical
multi‐polarization
effect
synergetic
magnetic
response,
N/S/F
harvest
broadest
bandwidth
8.28
(9.72–18
GHz)
2.55
mm,
covering
wide
frequency
range
almost
X
Ku
bands.
This
work
demonstrates
positive
impact
localized
multi‐defects
customization
on
expanding
microwave
absorption
bandwidth,
providing
valuable
insights
advanced
design
ultra‐broadband
absorbers.
