Abstract
In
this
study,
Co‐doped
SnO
2
is
synthesized
atop
the
hexagonal
CoS
template
(CoSS)
via
direct
air
calcination
of
as‐synthesized
SnS
(CoS)
nanosheets.
The
structural
evolution
facilitated
emergence
Co
2+
and
3+
states,
complemented
by
surface‐adsorbed
sulfur
oxyanions
(SO
4
2−
,
HSO
3
‐
SO
).
CoSS
deposited
over
carbon
cloth
(CoSS/CC)
exhibited
superior
bifunctional
HER
OER,
demonstrating
higher
stability
efficiency
than
their
CoS/CC
counterparts.
Notably,
CoSS/CC||CoSS/CC
shows
overall
water
splitting
at
a
minimum
cell
voltage
1.5
V,
significantly
lower
CoS/CC||CoS/CC.
Mechanistically,
states
serve
as
catalytically
active
sites
that
enhance
while
synergistic
interaction
between
promotes
activities.
Density
functional
theory
(DFT)
calculations
revealed
an
upshifted
d‐band
centre
(ɛ
d
)
enhanced
metal‐oxygen
covalency
(Δ)
in
CoSS,
with
charge
transfer
p‐d
hybridization.
ATR‐FTIR,
Raman,
XPS
investigations
confirmed
surface
reconstruction
CoSS/CC
electrodes
electrical
conductivity.
It
related
highly
strained
system
V
O
‐CoSS
has
more
unfilled
electronic
near
Fermi
level
F
to
facilitate
stable
HER/OER
intermediates.
Overall,
study
underscores
electrocatalytic
CoS/CC,
establishing
it
promising
candidate
for
efficient
splitting.
ACS Materials Letters,
Год журнала:
2025,
Номер
unknown, С. 524 - 543
Опубликована: Янв. 6, 2025
Electrocatalytic
water
splitting
is
pivotal
for
advancing
the
hydrogen
economy,
yet
conventional
stable-phase
catalysts
are
constrained
by
rigid
crystal
structures
and
electronic
states,
leading
to
fixed
active
sites,
limited
adaptability,
sluggish
kinetics.
Metastable
materials
emerge
as
promising
alternatives
due
their
structural
flexibility
tunable
properties;
however,
dynamic
regulatory
mechanisms
remain
underexplored.
This
review
uniquely
offers
a
comprehensive
analysis
of
metastable
catalysts,
emphasizing
how
factors
such
size,
phase
structure,
properties,
defects,
interfaces
significantly
enhance
catalytic
performance.
By
dissecting
range
(metals,
alloys,
oxides,
sulfides,
nitrides,
hydroxides),
we
elucidate
precise
modulation
strategies
that
improve
efficiency
stability.
Practical
applications
highlight
superior
adaptability
activity
compared
traditional
catalysts.
Addressing
key
challenges
technical
bottlenecks,
this
provides
innovative
insights
strategic
directions
optimizing
materials,
thereby
efficient
sustainable
energy
conversion
technologies.
Abstract
Developing
cost‐effective,
highly
efficient,
and
durable
bifunctional
electrocatalysts
for
water
electrolysis
remains
a
significant
challenge.
Nickel‐based
materials
have
shown
promise
as
catalysts,
but
their
efficiency
in
alkaline
electrolytes
is
still
lacking.
Fascinatingly,
Mott–Schottky
catalysts
can
fine‐tune
electron
density
at
interfaces,
boosting
intermediate
adsorption
facilitating
desorption
to
reduce
the
energy
barrier.
In
this
study,
iridium‐implanted
Ni/Ni
2
P
nanosheets
(Ir
SA
–Ni/Ni
P)
introduced,
which
are
delivered
from
metal–organic
framework
employ
them
devices.
This
catalyst
requires
small
54
mV
overpotential
hydrogen
evolution
reaction
(HER)
192
oxygen
(OER)
reach
10
mA·cm
−2
1.0
m
KOH
electrolyte.
Density
functional
theory
(DFT)
calculations
reveal
that
incorporation
of
Ir
atoms
with
enriched
interfaces
between
Ni
promote
active
sites
be
favorable
HER
OER.
discovery
highlights
most
likely
reactive
offers
valuable
blueprint
designing
efficient
stable
tailored
industrial‐scale
electrolysis.
The
‐Ni/Ni
electrode
exhibits
exceptional
current
outstanding
stability
single‐cell
anion‐exchange
membrane
electrolyzer.
The
interface
engineering
includes
intricate
procedures
for
the
development
of
heterostructures
and
heterojunctions,
modifying
composition
at
interface,
optimizing
interfacial
area
to
enhance
H
2
catalytic
performance.
Abstract
In
this
study,
Co‐doped
SnO
2
is
synthesized
atop
the
hexagonal
CoS
template
(CoSS)
via
direct
air
calcination
of
as‐synthesized
SnS
(CoS)
nanosheets.
The
structural
evolution
facilitated
emergence
Co
2+
and
3+
states,
complemented
by
surface‐adsorbed
sulfur
oxyanions
(SO
4
2−
,
HSO
3
‐
SO
).
CoSS
deposited
over
carbon
cloth
(CoSS/CC)
exhibited
superior
bifunctional
HER
OER,
demonstrating
higher
stability
efficiency
than
their
CoS/CC
counterparts.
Notably,
CoSS/CC||CoSS/CC
shows
overall
water
splitting
at
a
minimum
cell
voltage
1.5
V,
significantly
lower
CoS/CC||CoS/CC.
Mechanistically,
states
serve
as
catalytically
active
sites
that
enhance
while
synergistic
interaction
between
promotes
activities.
Density
functional
theory
(DFT)
calculations
revealed
an
upshifted
d‐band
centre
(ɛ
d
)
enhanced
metal‐oxygen
covalency
(Δ)
in
CoSS,
with
charge
transfer
p‐d
hybridization.
ATR‐FTIR,
Raman,
XPS
investigations
confirmed
surface
reconstruction
CoSS/CC
electrodes
electrical
conductivity.
It
related
highly
strained
system
V
O
‐CoSS
has
more
unfilled
electronic
near
Fermi
level
F
to
facilitate
stable
HER/OER
intermediates.
Overall,
study
underscores
electrocatalytic
CoS/CC,
establishing
it
promising
candidate
for
efficient
splitting.
