Abstract
Under
large
current
densities,
the
excessive
hydroxide
ion
(OH)
consumption
hampers
alkaline
water
splitting
involving
oxygen
evolution
reaction
(OER).
High
OH
concentration
(≈30
wt.%)
is
often
used
to
enhance
catalytic
activity
of
OER,
but
it
also
leads
higher
corrosion
in
practical
systems.
To
achieve
low
concentration,
catalysts
on
magnetic
frame
(CMF)
are
built
utilize
local
convection
induced
from
host
frame's
field
distributions.
This
way,
a
rate
can
be
achieved
relatively
lower
concentrations.
A
CMF
model
system
with
catalytically
active
CoFeO
x
nanograins
grown
Ni
foam
demonstrated.
The
OER
@NF
receives
≈90%
enhancement
under
400
mT
(900
mA
cm
−2
at
1.65
V)
compared
that
zero
field,
and
exhibits
remarkable
durability
over
120
h.
As
demonstration,
water‐splitting
performance
sees
maximum
45%
1
m
KOH
(700
2.4
V),
equivalent
same
electrode
more
corrosive
2
electrolyte.
Therefore,
catalyst‐on‐magnetic‐frame
strategy
make
efficient
use
by
harvesting
convection.
Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Авг. 6, 2024
Human
society
is
facing
increasingly
serious
problems
of
environmental
pollution
and
energy
shortage,
up
to
now,
achieving
high
NH3-SCR
activity
at
ultra-low
temperatures
(<150
°C)
remains
challenging
for
the
V-based
catalysts
with
V
content
below
2%.
In
this
study,
monoatomic
catalyst
under
weak
current-assisted
strategy
can
completely
convert
NOx
into
N2
temperature
1.36%,
which
shows
preeminent
turnover
frequencies
(TOF145
°C
=
1.97×10−3
s−1).
The
improvement
catalytic
performance
mainly
attributed
enhancement
catalysis
current
(ECWC)
rather
than
electric
field,
significantly
reduce
consumption
system
by
more
90%.
further
mechanism
research
ECWC
based
on
a
series
characterization
means
DFT
calculations
confirms
that
migrated
electrons
concentrate
around
single
atoms
increase
proportion
antibonding
orbitals,
make
V-O
chemical
bond
weaker
(electron
scissors
effect)
thus
accelerate
oxygen
circulation.
novel
in
present
work
potentially
apply
other
fields.
Achieving
NH3
selective
reduction
(below
150
challenge
catalysts.
Here
authors
explore
electron
effect
catalysis,
enables
exhibit
exceptional
denitration
temperatures.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(46)
Опубликована: Авг. 6, 2024
Abstract
The
rational
manipulation
of
the
surface
reconstruction
catalysts
is
a
key
factor
in
achieving
highly
efficient
water
oxidation,
but
it
challenge
due
to
complex
reaction
conditions.
Herein,
we
introduce
novel
situ
strategy
under
gradient
magnetic
field
form
catalytically
active
species
on
ferromagnetic/paramagnetic
CoFe
2
O
4
@CoBDC
core–shell
structure
for
electrochemical
oxygen
evolution
(OER).
We
demonstrate
that
Kelvin
force
from
cores’
local
modulates
shells’
reconstruction,
leading
higher
proportion
Co
2+
as
sites.
These
sites
with
optimized
electronic
configuration
exhibit
more
favorable
adsorption
energy
oxygen‐containing
intermediates
and
lower
activation
overall
catalytic
reaction.
As
result,
significant
enhancement
OER
performance
achieved
large
current
density
increment
about
128
%
at
1.63
V
an
overpotential
reduction
by
28
mV
10
mA
cm
−2
after
reconstruction.
Interestingly,
removing
external
field,
activity
could
persist
over
100
h.
This
work
showcases
directional
enhanced
oxidation.
Electrochemical
water
splitting
is
a
promising
method
for
generating
green
hydrogen
gas,
offering
sustainable
approach
to
addressing
global
energy
challenges.
However,
the
sluggish
kinetics
of
anodic
oxygen
evolution
reaction
(OER)
poses
great
obstacle
its
practical
application.
Recently,
increasing
attention
has
been
focused
on
introducing
various
external
stimuli
modify
OER
process.
Despite
significant
enhancement
in
catalytic
performance,
an
in-depth
understanding
origin
superior
activity
contributed
by
remains
elusive,
which
significantly
hinders
further
development
highly
efficient
and
durable
electrolyzed
devices.
Herein,
this
review
systematically
summarizes
recent
advancements
stimuli,
including
photon
irradiation,
applied
magnetic
field,
thermal
heating,
etc.,
boost
activities.
In
particular,
underlying
mechanisms
promote
species
transfer,
electronic
structure
electrocatalysts,
accelerate
structural
reconstruction
are
highlighted.
Additionally,
applications
other
electrocatalytic
reactions
also
presented.
Finally,
several
remaining
challenges
future
opportunities
discussed,
providing
insights
that
could
study
support
rational
design
storage
conversion
Advanced Energy Materials,
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 5, 2025
Abstract
Electrocatalytic
CO
2
reduction
(CO
RR)
is
rapidly
emerging
as
a
promising
sustainable
strategy
for
transforming
into
valuable
fuels
and
chemical
feedstocks,
crucial
step
toward
carbon‐neutral
society.
The
efficiency,
selectivity,
stability
of
RR
are
heavily
influenced
by
the
chosen
catalyst
operating
conditions
used.
Despite
substantial
advances
in
development
catalysts,
there
scarcity
comprehensive
reviews
focusing
on
influence
different
environments
performance.
This
review
offers
detailed
examination
internal
external
environmental
control
strategies
designed
to
enhance
efficiency.
fundamental
reaction
mechanisms
through
situ
operational
techniques,
paired
with
theoretical
analyses,
discussed
while
also
identifying
key
challenges
future
research
directions
technology.
By
delivering
overview
current
state
field,
this
highlights
critical
role
control,
mechanistic
insights,
practical
considerations
needed
successful
commercialization
The
use
of
magnetic
fields
as
external
stimuli
to
improve
the
kinetics
electrochemical
reactions
is
attracting
substantial
attention,
given
their
potential
reduce
energy
losses.
Despite
recent
reports
showing
a
positive
effect
on
catalytic
performance
upon
applying
field
working
electrode,
there
are
still
many
uncertainties
and
lack
experimental
evidence
correlating
presence
electrocatalytic
performance.
Here,
we
present
combination
spectroscopic
tools
that
demonstrate
how
an
alters
reaction
mechanism
oxygen
evolution
(OER),
accelerating
overall
Ni4FeOx
electrode.
Complementary
has
been
gathered
supporting
participation
this
microscopic
effect.
Electrochemical
impedance
spectroscopy
(EIS)
points
speed-up
intrinsic
kinetics,
independent
other
indirect
effects.
In
same
direction,
spectro-electrochemical
fingerprint
intermediate
species
appear
during
cycle,
detected
under
operando
conditions,
indicates
change
in
order
function
hole
accumulation.
All
these
data
confirm
direct
influence
at
origin
magnetically
enhanced
OER.