Abstract
Construction
of
heterojunctions
is
an
effective
strategy
to
enhanced
electrocatalytic
oxygen
evolution
reaction
(OER),
but
the
structural
active
phases
and
synergistic
mechanism
still
lack
in‐depth
understanding.
Here,
FeOOH/Ni
3
S
2
heterostructure
supported
on
nickel
foam
(NF)
through
a
two‐step
hydrothermal‐chemical
etching
method
reported.
In
situ
Raman
spectroscopy
study
surface
reconstruction
behaviors
/NF
indicates
that
Ni
can
be
rapidly
converted
NiOOH,
accompanied
by
phase
transition
from
α
‐FeOOH
β
during
OER
process.
Importantly,
deep
analysis
Ni─O
bond
reveals
FeOOH
regulate
lattice
disorder
NiOOH
for
improved
catalytic
activity.
Density
functional
theory
(DFT)
calculations
further
confirm
NiOOH/FeOOH
possess
strengthened
adsorption
O‐containing
intermediates,
as
well
lower
energy
barrier
toward
OER.
As
result,
exhibits
promising
activity
stability
in
alkaline
conditions,
requiring
overpotential
268
mV
@
100
mA
cm
−2
long‐term
over
200
h
at
current
density
.
This
work
provides
new
perspective
understanding
heterogeneous
electrocatalysts
Nickel-iron
based
hydr(oxy)oxides
have
been
well
recognized
as
one
of
the
best
oxygen-evolving
catalysts
in
alkaline
water
electrolysis.
A
crucial
problem,
however,
is
that
iron
leakage
during
prolonged
operation
would
lead
to
oxygen
evolution
reaction
(OER)
deactivation
over
time,
especially
under
large
current
densities.
Here,
NiFe-based
Prussian
blue
analogue
(PBA)
designed
a
structure-flexible
precursor
for
navigating
an
electrochemical
self-reconstruction
(ECSR)
with
Fe
cation
compensation
fabricate
highly
active
hydr(oxy)oxide
(NiFeO
Advanced Energy Materials,
Год журнала:
2023,
Номер
13(35)
Опубликована: Июль 21, 2023
Abstract
Deep
insight
into
electrochemical
reconstruction
aids
in
the
decoding
of
electrocatalytic
mechanisms
and
development
design
principles
for
advanced
catalysts.
Despite
recent
achievements,
research
concerning
cathodic
is
still
lacking
compared
to
anodic
variety.
This
work
captures
electroreductive
dynamics
over
bimetal
Ni–Mo
sulfide
by
various
in/ex
situ
techniques,
whereby
steered
with
ion
regulation
achieve
a
heterogeneous
Ni–Mo–Fe
ternary
metal
hydroxysulfide
(NMFSOH)
as
robust
hydrogen‐evolving
catalyst
that
competent
industrial‐level
water
electrolysis.
The
thermodynamically
adaptive
heterosynergism
resultant
NMFSOH
can
coordinate
dissociation
hydrogenation
alkaline
hydrogen
evolution
reaction
even
at
high
current
densities.
A
flow‐type
electrolyzer
dual
electrodes
affords
an
electricity
consumption
3.99
kW
h
Nm
−3
electricity‐to‐hydrogen
efficiency
88.7%,
manifesting
its
competitive
cost‐effectiveness
toward
practical
applications.
study
showcases
ion‐regulatory
effective
strategy
construct
high‐performance
electrocatalysts.
Developing
robust
nonprecious
metal‐based
electrocatalysts
toward
hydrogen
evolution
reaction
is
crucial
for
large‐scale
production
via
electrochemical
water
splitting.
Herein,
surface
high‐entropy
NiFeCoCuTi
alloy
on
column‐nanostructured
nanoporous
Ni
skeleton
reported
as
multisite
electrocatalyst
highly
efficient
in
nonacidic
environments
by
making
use
of
heterogeneous
atoms
with
distinct
and
hydroxyl
adsorption
behaviors
to
accelerate
dissociation
mediate
intermediates
combination
into
molecules.
Associated
the
that
facilitates
electron
transfer/mass
transportation
enables
accessible
abundant
electroactive
sites,
self‐supported
monolithic
electrode
exhibits
superior
(HER)
electrocatalysis,
low
onset
overpotentials
Tafel
slopes.
It
only
takes
overpotential
≈209
mV
deliver
ultrahigh
current
density
2
A
cm
−2
,
along
exceptional
stability
more
than
240
h,
1
m
KOH
electrolyte.
These
outstanding
properties
make
(HEA)
attractive
candidate
cathode
material
electrolysis
suggest
HEAs
ideal
platform
develop
electrocatalysts.
Abstract
Construction
of
heterojunctions
is
an
effective
strategy
to
enhanced
electrocatalytic
oxygen
evolution
reaction
(OER),
but
the
structural
active
phases
and
synergistic
mechanism
still
lack
in‐depth
understanding.
Here,
FeOOH/Ni
3
S
2
heterostructure
supported
on
nickel
foam
(NF)
through
a
two‐step
hydrothermal‐chemical
etching
method
reported.
In
situ
Raman
spectroscopy
study
surface
reconstruction
behaviors
/NF
indicates
that
Ni
can
be
rapidly
converted
NiOOH,
accompanied
by
phase
transition
from
α
‐FeOOH
β
during
OER
process.
Importantly,
deep
analysis
Ni─O
bond
reveals
FeOOH
regulate
lattice
disorder
NiOOH
for
improved
catalytic
activity.
Density
functional
theory
(DFT)
calculations
further
confirm
NiOOH/FeOOH
possess
strengthened
adsorption
O‐containing
intermediates,
as
well
lower
energy
barrier
toward
OER.
As
result,
exhibits
promising
activity
stability
in
alkaline
conditions,
requiring
overpotential
268
mV
@
100
mA
cm
−2
long‐term
over
200
h
at
current
density
.
This
work
provides
new
perspective
understanding
heterogeneous
electrocatalysts
