Materials Today Physics,
Journal Year:
2024,
Volume and Issue:
46, P. 101481 - 101481
Published: June 13, 2024
Oxycarbide
MXenes
were
recently
experimentally
identified,
opening
up
the
possibility
of
a
vast
majority
carbon-based
synthesised
to
date
being
in
fact
oxycarbides,
wherein
some
substitutional
oxygen
atoms
are
present
amid
layers
that
previously
thought
contain
carbon
only.
Here,
using
an
approach
based
on
density-functional
theory,
we
study
structural,
energetic
and
electronic
properties
subsurface
X
form
M2XT2,
with
M
=
Ti,
V;
C,
N;
T
none,
O
or
F.
According
calculations,
is
thermodynamically
stable
any
concentration
all
analysed
MXenes.
Subsurface
Ti2C
MXene
driven
towards
surface,
leaving
behind
vacancies
creating
local
surface
terminations.
Given
this
process
involves
very
low
energy
barrier,
predict
that,
under
conditions
suitable
for
eliminating
termination
MXenes,
many
should
occur.
The
O-terminated
carbide
Ti2CO2
V2CO2,
their
hexagonal
symmetry
threshold
amount
O,
around
75
%,
which
above
maximum
observed
concentration,
65
%.
F
stabilizes
structure
no
longer
distort
regardless
presence
oxygen.
This
suggests
synthesis
routes
fluorine-containing
compounds
most
indicated
synthesising
nitride
PBE
functional
predicts
semiconductor
characteristics
be
lost
even
percentage
as
6
lowest
considered
work.
hybrid
HSE06
oxycarbide
material
remain
semiconductor,
but
significantly
lowered
band
gap
increasing
content.
Nevertheless,
both
functionals
agree
mixture
C
between
Ti
increases
its
conductivity.
To
best
our
knowledge,
has
never
been
confirmed
behave
probably
because
real
samples
Nano-Micro Letters,
Journal Year:
2024,
Volume and Issue:
16(1)
Published: June 6, 2024
Abstract
With
the
development
of
science
and
technology,
scale
industrial
production
continues
to
grow,
types
quantities
gas
raw
materials
used
in
produced
during
process
are
also
constantly
increasing.
These
gases
include
flammable
explosive
gases,
even
contain
toxic
gases.
Therefore,
it
is
very
important
necessary
for
sensors
detect
monitor
these
quickly
accurately.
In
recent
years,
a
new
two-dimensional
material
called
MXene
has
attracted
widespread
attention
various
applications.
Their
abundant
surface
functional
groups
sites,
excellent
current
conductivity,
tunable
chemistry,
outstanding
stability
make
them
promising
sensor
Since
birth
materials,
researchers
have
utilized
efficient
convenient
solution
etching
preparation,
high
flexibility,
easily
functionalize
with
other
prepare
composites
sensing.
This
opened
chapter
high-performance
sensing
provided
approach
advanced
research.
However,
previous
reviews
on
MXene-based
composite
only
focused
performance
sensing,
without
systematically
explaining
mechanisms
generated
by
different
as
well
summarizing
predicting
advantages
disadvantages
materials.
article
latest
progress
application
Firstly,
brief
summary
was
given
commonly
methods
preparing
device
structures,
followed
an
introduction
key
attributes
related
performance.
focuses
such
MXene/graphene,
MXene/Metal
oxide,
MXene/Transition
metal
sulfides
(TMDs),
MXene/Metal–organic
framework
(MOF),
MXene/Polymer.
It
summarizes
discusses
possible
Finally,
future
directions
inroads
MXenes-based
presented
discussed.
Accounts of Chemical Research,
Journal Year:
2024,
Volume and Issue:
57(16), P. 2395 - 2413
Published: Aug. 5, 2024
ConspectusGas
sensors
are
used
in
various
applications
to
sense
toxic
gases,
mainly
for
enhanced
safety.
Resistive
particularly
popular
owing
their
ability
detect
trace
amounts
of
high
stability,
fast
response
times,
and
affordability.
Semiconducting
metal
oxides
commonly
employed
the
fabrication
resistive
gas
sensors.
However,
these
often
require
working
temperatures,
bringing
about
increased
energy
consumption
reduced
selectivity.
Furthermore,
they
do
not
have
enough
flexibility,
performance
is
significantly
decreased
under
bending,
stretching,
or
twisting.
To
address
challenges,
alternative
materials
capable
operating
at
lower
temperatures
with
flexibility
needed.
Two-dimensional
(2D)
such
as
MXenes
transition-metal
dichalcogenides
(TMDs)
offer
surface
area
conductivity
unique
2D
structure,
making
them
promising
candidates
realization
Nevertheless,
sensing
pristine
form
typically
weak
unacceptable,
terms
response,
selectivity,
recovery
time
(
Small,
Journal Year:
2023,
Volume and Issue:
20(21)
Published: Dec. 14, 2023
Abstract
Defect
engineering
is
recognized
as
an
attractive
method
for
modulating
the
electronic
structure
and
physicochemical
characteristics
of
carbon
materials.
Exploiting
heteroatom‐doped
porous
with
copious
active
sites
has
attracted
great
attention
capacitive
deionization
(CDI).
However,
traditional
methods
often
rely
on
utilization
additional
heteroatom
sources
strong
corrosive
activators,
suffering
from
low
doping
efficiency,
insufficient
level,
potential
biotoxicity.
Herein,
hydrogen‐bonded
organic
frameworks
(HOFs)
are
employed
precursors
to
synthesize
N,
O
co‐doped
via
a
simple
green
reverse
defect
strategy,
achieving
controllable
heavy
heteroatoms.
The
co‐doping
triggers
significant
pseudocapacitive
contribution
surface
pore
supports
formation
electric
double
layer.
Therefore,
when
HOF‐derived
used
CDI
electrodes,
superior
salt
adsorption
capacity
32.29
±
1.42
mg
g
−1
outstanding
maximum
rate
10.58
0.46
min
at
1.6
V
in
500
L
NaCl
solution
achieved,
which
comparable
those
state‐of‐the‐art
carbonaceous
electrodes.
This
work
exemplifies
effectiveness
nitrogen‐heavy
strategy
improving
structure,
shedding
light
further
development
rational
designed
electrode
materials
CDI.
