Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(29), С. 20379 - 20390
Опубликована: Июль 16, 2024
Scarce
and
expensive
iridium
oxide
is
still
the
cornerstone
catalyst
of
polymer-electrolyte
membrane
electrolyzers
for
green
hydrogen
production
because
its
exceptional
stability
under
industrially
relevant
oxygen
evolution
reaction
(OER)
conditions.
Earth-abundant
transition
metal
oxides
used
this
task,
however,
show
poor
long-term
stability.
We
demonstrate
here
use
nitrogen-doped
cobalt
as
an
effective
substitute.
The
exhibits
a
low
overpotential
240
mV
at
10
mA
cm–2
negligible
activity
decay
after
1000
h
operation
in
alkaline
electrolyte.
Incorporation
nitrogen
dopants
not
only
triggers
OER
mechanism
switched
from
traditional
adsorbate
route
to
lattice
oxidation
but
also
achieves
nonbonding
(ONB)
states
electron
donors,
thereby
preventing
structural
destabilization.
In
practical
anion-exchange
water
electrolyzer,
anode
delivers
current
density
1.78
V
electrical
efficiency
47.8
kW-hours
per
kilogram
hydrogen.
Nature Communications,
Год журнала:
2023,
Номер
14(1)
Опубликована: Апрель 4, 2023
Rational
design
efficient
transition
metal-based
electrocatalysts
for
oxygen
evolution
reaction
(OER)
is
critical
water
splitting.
However,
industrial
water-alkali
electrolysis
requires
large
current
densities
at
low
overpotentials,
always
limited
by
intrinsic
activity.
Herein,
we
report
hierarchical
bimetal
nitride/hydroxide
(NiMoN/NiFe
LDH)
array
as
model
catalyst,
regulating
the
electronic
states
and
tracking
relationship
of
structure-activity.
As-activated
NiMoN/NiFe
LDH
exhibits
industrially
required
density
1000
mA
cm-2
overpotential
266
mV
with
250
h
stability
OER.
Especially,
in-situ
electrochemical
spectroscopic
reveals
that
heterointerface
facilitates
dynamic
structure
to
optimize
structure.
Operando
impedance
spectroscopy
implies
accelerated
OER
kinetics
intermediate
due
fast
charge
transport.
The
mechanism
revealed
combination
theoretical
experimental
studies,
indicating
as-activated
follows
lattice
oxidation
kinetics.
This
work
paves
an
avenue
develop
catalysts
via
tuning
states.
Nature Communications,
Год журнала:
2023,
Номер
14(1)
Опубликована: Сен. 27, 2023
The
oxygen
evolution
reaction
is
known
to
be
a
kinetic
bottleneck
for
water
splitting.
Triggering
the
lattice
oxidation
mechanism
(LOM)
can
break
theoretical
limit
of
conventional
adsorbate
and
enhance
kinetics,
yet
unsatisfied
stability
remains
grand
challenge.
Here,
we
report
high-entropy
MnFeCoNiCu
layered
double
hydroxide
decorated
with
Au
single
atoms
O
vacancies
(AuSA-MnFeCoNiCu
LDH),
which
not
only
displays
low
overpotential
213
mV
at
10
mA
cm-2
high
mass
activity
732.925
A
g-1
250
in
1.0
M
KOH,
but
also
delivers
good
700
h
continuous
operation
~100
cm-2.
Combining
advanced
spectroscopic
techniques
density
functional
theory
calculations,
it
demonstrated
that
synergistic
interaction
between
incorporated
leads
an
upshift
2p
band
weakens
metal-O
bond,
thus
triggering
LOM,
reducing
energy
barrier,
boosting
intrinsic
activity.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(24)
Опубликована: Март 21, 2023
The
development
of
productive
catalysts
for
the
oxygen
evolution
reaction
(OER)
remains
a
major
challenge
requiring
significant
progress
in
both
mechanism
and
material
design.
Conventionally,
thermodynamic
barrier
lattice
oxidation
(LOM)
is
lower
than
that
absorbate
(AEM)
because
former
can
overcome
certain
limitations.
However,
controlling
OER
pathway
from
AEM
to
LOM
by
exploiting
intrinsic
properties
catalyst
challenging.
Herein,
we
incorporated
F
anions
into
vacancies
spinel
ZnCo2
O4
established
link
between
electronic
structure
catalytic
mechanism.
Theoretical
density
calculations
revealed
upshifts
O
2p
center
activates
redox
capability
O,
successfully
triggering
pathway.
Moreover,
high
electronegativity
favourable
balancing
residual
protonation,
which
stabilize
catalyst.
Advanced Functional Materials,
Год журнала:
2023,
Номер
33(45)
Опубликована: Сен. 1, 2023
Abstract
Oxygen
evolution
reaction
(OER)
remains
a
bottleneck
for
electrocatalytic
water‐splitting
to
generate
hydrogen.
However,
the
traditional
adsorbed
mechanism
(AEM)
possesses
sluggish
kinetics
due
scaling
relationship,
while
lattice
oxygen
(LOM)
triggers
an
unstable
structure
escaping
of
oxygen.
Herein,
proof‐of‐concept
Fe‐Co(OH)
2
/Fe
O
3
heterostructure
is
put
forward,
where
following
AEM
can
complete
rapidly
deprotonation
process
Fe
LOM
trigger
O─O
coupling
step.
Combining
theoretical
and
experimental
investigation
confirmed
that
redistributed
space‐charge
junction
optimize
synergistically
oxygen,
facilitate
synchronously
OER
activity
stability.
As
result,
shows
excellent
performance
with
low
overpotential
only
219
249
mV
reach
current
density
10
100
mA
cm
−2
.
Specifically,
electrocatalyst
maintains
long‐term
stability
h
at
large
This
work
paves
avenue
break
through
limit
conventional
mechanism.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(40)
Опубликована: Авг. 15, 2023
Abstract
Heteroatom
doping
has
emerged
as
a
highly
effective
strategy
to
enhance
the
activity
of
metal‐based
electrocatalysts
toward
oxygen
evolution
reaction
(OER).
It
is
widely
accepted
that
does
not
switch
OER
mechanism
from
adsorbate
(AEM)
lattice‐oxygen‐mediated
(LOM),
and
enhanced
attributed
optimized
binding
energies
intermediates.
However,
this
seems
inconsistent
with
fact
overpotential
doped
(<300
mV)
considerably
smaller
than
limit
AEM
(>370
mV).
To
determine
origin
inconsistency,
we
select
phosphorus
(P)‐doped
nickel‐iron
mixed
oxides
model
observe
enhances
covalency
metal‐oxygen
bonds
drive
pathway
transition
LOM,
thereby
breaking
adsorption
linear
relation
between
*OH
*OOH
in
AEM.
Consequently,
obtained
P‐doped
display
small
237
mV
at
10
mA
cm
−2
.
Beyond
P,
similar
also
observed
on
sulfur
doping.
These
findings
offer
new
insights
into
substantially
originating
heteroatom
Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Фев. 3, 2024
Abstract
Oxygen
evolution
reaction
(OER)
is
critical
to
renewable
energy
conversion
technologies,
but
the
structure-activity
relationships
and
underlying
catalytic
mechanisms
in
catalysts
are
not
fully
understood.
We
herein
demonstrate
a
strategy
promote
OER
with
simultaneously
achieved
lattice
oxygen
activation
enhanced
local
electric
field
by
dual
doping
of
cations
anions.
Rough
arrays
Fe
F
co-doped
CoO
nanoneedles
constructed,
low
overpotential
277
mV
at
500
mA
cm
−2
achieved.
The
dually
doped
could
cooperatively
tailor
electronic
properties
CoO,
leading
improved
metal-oxygen
covalency
stimulated
activation.
Particularly,
induces
synergetic
effect
tip
enhancement
proximity
effect,
which
effectively
concentrates
OH
−
ions,
optimizes
barrier
promotes
O
2
desorption.
This
work
demonstrates
conceptual
couple
for
effective
electrocatalytic
water
oxidation.
Graphite
phased
carbon
nitride
(g-C3
N4
)
has
attracted
extensive
attention
attributed
to
its
non-toxic
nature,
remarkable
physical-chemical
stability,
and
visible
light
response
properties.
Nevertheless,
the
pristine
g-C3
suffers
from
rapid
photogenerated
carrier
recombination
unfavorable
specific
surface
area,
which
greatly
limit
catalytic
performance.
Herein,
0D/3D
Cu-FeOOH/TCN
composites
are
constructed
as
photo-Fenton
catalysts
by
assembling
amorphous
Cu-FeOOH
clusters
on
3D
double-shelled
porous
tubular
(TCN)
fabricated
through
one-step
calcination.
Combined
density
functional
theory
(DFT)
calculations,
synergistic
effect
between
Cu
Fe
species
could
facilitate
adsorption
activation
of
H2
O2
,
separation
transfer
charges
effectively.
Thus,
acquire
a
high
removal
efficiency
97.8%,
mineralization
rate
85.5%
first-order
constant
k
=
0.0507
min-1
for
methyl
orange
(MO)
(40
mg
L-1
in
reaction
system,
is
nearly
10
times
21
higher
than
those
FeOOH/TCN
(k
0.0047
TCN
0.0024
),
respectively,
indicating
universal
applicability
desirable
cyclic
stability.
Overall,
this
work
furnishes
novel
strategy
developing
heterogeneous
based
nanotubes
practical
wastewater
treatment.
