Realizing
low-temperature
detection
of
NO2
is
crucial
to
protecting
the
environment
and
human
health.
In
this
study,
SnS2/SnO2
hexagonal
nanosheets
with
an
average
size
630
nm
were
synthesized
by
a
two-step
process.
Subsequently,
Ag
nanoparticles
modified
on
surface
form
Ag-modified
nanoheterojunctions.
Compared
SnS2
sensors,
Ag/SnS2/SnO2-based
sensors
have
better
gas-sensing
performance
at
optimum
operating
temperature
100
°C,
including
higher
response,
stability,
excellent
selectivity
NO2.
The
response
value
Ag/SnS2/SnO2
sensor
7
ppm
°C
56.4,
which
four
times
than
that
sensor.
outstanding
sensing
properties
can
be
due
combination
modification
formation
SnS2–SnO2
heterojunction.
Advanced Materials Technologies,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 8, 2025
Abstract
Methane
(CH
4
)
serves
as
a
commonly
utilized
fuel
gas
in
various
industrial
and
everyday
settings.
Given
its
flammable,
explosive,
greenhouse
nature,
the
real‐time
monitoring
of
concentration
air
holds
vital
importance
across
practical
applications.
The
tetrahedral
structure
methane
molecules
features
high
bond
energies,
posing
significant
challenge
for
chemical
detection
over
metal
oxide‐sensitive
layers.
In
this
research,
multicomponent
assembly
method
is
used
to
synthesize
ordered
mesoporous
tin
oxide
(SnO
2
with
uniform
large
mesopores
(≈
10
nm)
pore
wall
functionalized
Pd
x
Pt
nanoalloys
2.5
nm),
due
unusual
C–H
activation
capabilities
semiconducting
properties
SnO
,
obtained
Pt@m‐SnO
fabricate
sensors
which
showcases
wide
applicability
range
detecting
concentrations
ranging
from
50
20
000
ppm
at
400
°C,
it
yields
substantial
CH
response
9.19
(1000
ppm)
an
ultralow
limit
value
175.9
ppb.
Furthermore,
sensor
successfully
incorporated
into
portable
device,
evidencing
capability
accurate
real‐world
scenarios.
The
construction
of
crystalline-amorphous
heterogeneous
phase
interfaces
is
an
effective
strategy
to
enhance
their
surface
active
sites.
We
successfully
synthesised
amorphous
Pt-crystalline
Cu
(aPtcCu)
nanospheres
for
ultrasensitive
H2
detection.
Cu2+
first
reduced
in
the
oleylamine−ascorbic
acid
(OAm-AA)
solvent
system
due
inhibition
Pt
reduction.
Next
Pt2+
by
electrocoupling
substitution
already
and
amorphisation
achieved
strong
OAm
adsorption.
gas
sensing
test
results
show
that
aPtcCu/ZnO
sensor
has
higher
response
lower
working
temperature
(160
oC)
than
Pt/ZnO
(180
ZnO
(240
oC).
Moreover,
can
detect
as
low
2
ppm
response/recovery
time
only
s/6
s.
significantly
sensitization
characteristic
aPtcCu
be
attributed
following:
1)
more
site
on
Pt;
2)
crystalline/amorphous
heterophase
interface
separates
electrons
holes,
which
further
catalytic
activity
aPtcCu;
3)
Pt4+
↔
accelerates
reaction
surface.
prepared
expected
a
candidate
monitoring
hydrogen
leakage,
provides
new
direction
application
amorphous/crystalline
sensitizers
sensors.
Chemosensors,
Journal Year:
2025,
Volume and Issue:
13(4), P. 121 - 121
Published: April 1, 2025
Notwithstanding
the
success
of
SnO2
as
a
fundamental
material
for
gas
sensing,
it
has
often
been
criticized
its
cross-sensitivity
and
high
operational
temperatures.
Therefore,
in
this
study,
RF-sputtered
thin
films
were
subjected
to
modification
process
through
doping
with
rare
earth
element,
dysprosium
(Dy),
subsequently
deposited
onto
two
different
types
substrates:
alumina
glass
substrates.
All
underwent
comprehensive
series
characterizations
aimed
at
ensuring
their
suitability
NO2
sensors.
The
levels
ranged
from
1
7
wt.%
increments
2%
(wt.%).
X-ray
patterns
showed
that
all
exhibited
tetragonal
rutile
structure
SnO2.
optical
band
gap
energy
(Eg)
increased
Dy
doping,
while
Urbach
decreased
doping.
Field
emission
scanning
electron
microscopy
(FESEM)
revealed
highly
compacted
grainy
surfaces
roughness
substrate
films,
which
also
higher
resistivity
Energy-dispersive
spectroscopy
(EDX)
analyses
confirmed
stoichiometry
both
films.
Gas
sensing
tests
conducted
operating
temperatures,
where
highest
response
nitrogen
dioxide,
over
42%,
was
recorded
dopant
level
250
°C.
Moreover,
sensor’s
selectivity
toward
dioxide
traces
evaluated
by
introducing
interfering
gases
concentrations.
However,
sensors
significant
responses
when
operated
room
temperature.
Also,
we
have
demonstrated
stability
is
related
temperature
ratio.
Hence,
detailed
discussion
gas-sensing
mechanisms
undertaken
gain
deeper
insight
into
sensitivity
Dy-doped
layer.
