Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
60(37), С. 20535 - 20542
Опубликована: Июль 21, 2021
Abstract
The
Co‐based
electrocatalyst
is
among
the
most
promising
candidates
for
electrochemical
oxidation
of
5‐hydroxymethylfurfural
(HMF).
However,
intrinsic
active
sites
and
detailed
mechanism
this
catalyst
remains
unclear.
We
combine
experimental
evidence
a
theoretical
study
to
show
that
electrogenerated
Co
3+
4+
species
act
as
chemical
oxidants
but
with
distinct
roles
in
selective
HMF
oxidation.
It
found
only
capable
oxidizing
formyl
group
produce
carboxylate
while
required
initial
hydroxyl
significantly
faster
kinetics.
As
result,
product
distribution
shows
explicit
dependence
on
states
production
5‐hydroxymethyl‐2‐furancarboxylic
acid
(HMFCA)
2,5‐furandicarboxylic
(FDCA)
are
achieved
by
tuning
applied
potential.
This
work
offers
essential
mechanistic
insight
Co‐catalyzed
organic
reactions
might
guide
design
more
efficient
electrocatalysts.
Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
61(1)
Опубликована: Июнь 17, 2021
Water
electrolysis
that
results
in
green
hydrogen
is
the
key
process
towards
a
circular
economy.
The
supply
of
sustainable
electricity
and
availability
oxygen
evolution
reaction
(OER)
electrocatalysts
are
main
bottlenecks
for
large-scale
production
hydrogen.
A
broad
range
OER
have
been
explored
to
decrease
overpotential
boost
kinetics
this
sluggish
half-reaction.
Co-,
Ni-,
Fe-based
catalysts
considered
be
potential
candidates
replace
noble
metals
due
their
tunable
3d
electron
configuration
spin
state,
versatility
terms
crystal
electronic
structures,
as
well
abundance
nature.
This
Review
provides
some
basic
principles
water
electrolysis,
aspects
OER,
significant
criteria
development
catalysts.
It
also
insights
on
recent
advances
oxides
brief
perspective
challenges
electrolysis.
Nature Communications,
Год журнала:
2021,
Номер
12(1)
Опубликована: Май 24, 2021
Abstract
Developing
efficient
and
stable
earth-abundant
electrocatalysts
for
acidic
oxygen
evolution
reaction
is
the
bottleneck
water
splitting
using
proton
exchange
membrane
electrolyzers.
Here,
we
show
that
nanocrystalline
CeO
2
in
a
Co
3
O
4
/CeO
nanocomposite
can
modify
redox
properties
of
enhances
its
intrinsic
activity,
combine
electrochemical
structural
characterizations
including
kinetic
isotope
effect,
pH-
temperature-dependence,
situ
Raman
ex
X-ray
absorption
spectroscopy
analyses
to
understand
origin.
The
local
bonding
environment
be
modified
after
introduction
,
which
allows
III
species
easily
oxidized
into
catalytically
active
IV
species,
bypassing
potential-determining
surface
reconstruction
process.
displays
comparable
stability
thus
breaks
activity/stability
tradeoff.
This
work
not
only
establishes
an
catalysts
reaction,
but
also
provides
strategies
designing
more
other
reactions.
Nature Communications,
Год журнала:
2021,
Номер
12(1)
Опубликована: Авг. 17, 2021
Abstract
Plastic
wastes
represent
a
largely
untapped
resource
for
manufacturing
chemicals
and
fuels,
particularly
considering
their
environmental
biological
threats.
Here
we
report
electrocatalytic
upcycling
of
polyethylene
terephthalate
(PET)
plastic
to
valuable
commodity
(potassium
diformate
terephthalic
acid)
H
2
fuel.
Preliminary
techno-economic
analysis
suggests
the
profitability
this
process
when
ethylene
glycol
(EG)
component
PET
is
selectively
electrooxidized
formate
(>80%
selectivity)
at
high
current
density
(>100
mA
cm
−2
).
A
nickel-modified
cobalt
phosphide
(CoNi
0.25
P)
electrocatalyst
developed
achieve
500
1.8
V
in
membrane-electrode
assembly
reactor
with
>80%
Faradaic
efficiency
selectivity
formate.
Detailed
characterizations
reveal
in-situ
evolution
CoNi
P
catalyst
into
low-crystalline
metal
oxy(hydroxide)
as
an
active
state
during
EG
oxidation,
which
might
be
responsible
its
advantageous
performances.
This
work
demonstrates
sustainable
way
implement
waste
value-added
products.
Energy & Environmental Science,
Год журнала:
2021,
Номер
14(9), С. 4647 - 4671
Опубликована: Янв. 1, 2021
Lattice
oxygen
redox
chemistry
in
solid-state
electrocatalysts
rationalizes
the
remarkable
OER
activity
by
lattice
oxygen-mediated
mechanism.
Here
we
elucidate
fundamental
principle
of
this
mechanism
and
summarize
recently
related
developments.
Chemical Reviews,
Год журнала:
2023,
Номер
123(9), С. 6257 - 6358
Опубликована: Март 21, 2023
The
oxygen
evolution
reaction
(OER)
and
reduction
(ORR)
are
core
steps
of
various
energy
conversion
storage
systems.
However,
their
sluggish
kinetics,
i.e.,
the
demanding
multielectron
transfer
processes,
still
render
OER/ORR
catalysts
less
efficient
for
practical
applications.
Moreover,
complexity
catalyst–electrolyte
interface
makes
a
comprehensive
understanding
intrinsic
mechanisms
challenging.
Fortunately,
recent
advances
in
situ/operando
characterization
techniques
have
facilitated
kinetic
monitoring
under
conditions.
Here
we
provide
selected
highlights
mechanistic
studies
with
main
emphasis
placed
on
heterogeneous
systems
(primarily
discussing
first-row
transition
metals
which
operate
basic
conditions),
followed
by
brief
outlook
molecular
catalysts.
Key
sections
this
review
focused
determination
true
active
species,
identification
sites,
reactive
intermediates.
For
in-depth
insights
into
above
factors,
short
overview
metrics
accurate
characterizations
is
provided.
A
combination
obtained
time-resolved
information
reliable
activity
data
will
then
guide
rational
design
new
Strategies
such
as
optimizing
restructuring
process
well
overcoming
adsorption-energy
scaling
relations
be
discussed.
Finally,
pending
current
challenges
prospects
toward
development
homogeneous
presented.
Nature Communications,
Год журнала:
2022,
Номер
13(1)
Опубликована: Фев. 1, 2022
Computational
calculations
and
experimental
studies
reveal
that
the
CoOOH
phase
intermediate-spin
(IS)
state
are
key
factors
for
realizing
efficient
Co-based
electrocatalysts
oxygen
evolution
reaction
(OER).
However,
according
to
thermodynamics,
general
cobalt
oxide
converts
CoO2
under
OER
condition,
retarding
kinetics.
Herein,
we
demonstrate
a
simple
scalable
strategy
fabricate
electrodes
with
maintaining
Fe-CoOOH
an
IS
OER.
The
changes
of
spin
states
were
uncovered
by
combining
in-situ/operando
X-ray
based
absorption
spectroscopy
Raman
spectroscopy.
Electrochemical
reconstruction
chalcogenide
treated
Co
foam
affords
highly
enlarged
active
surface
conferred
excellent
catalytic
activity
stability
in
large-scale
water
electrolyzer.
Our
findings
meaningful
calculated
results
experimentally
verified
through
operando
analyses.
It
also
proposes
new
electrode
fabrication
confirms
importance
real
phases
particular
condition.
Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
60(21), С. 11841 - 11846
Опубликована: Март 19, 2021
Abstract
The
development
of
efficient
and
low‐cost
electrocatalysts
toward
the
oxygen
evolution
reaction
(OER)
is
critical
for
improving
efficiency
several
electrochemical
energy
conversion
storage
devices.
Here,
we
report
an
elaborate
design
synthesis
porous
Co‐based
trimetallic
spinel
oxide
nanoboxes
(NiCo
2−
x
Fe
O
4
NBs)
by
a
novel
metal‐organic
framework
engaged
strategy,
which
involves
chemical
etching,
cation
exchange,
subsequent
thermal
oxidation
processes.
Owing
to
structural
compositional
advantages,
optimized
NiCo
NBs
(
about
0.117)
deliver
superior
electrocatalytic
performance
OER
with
overpotential
274
mV
at
10
mA
cm
−2
,
small
Tafel
slope
42
dec
−1
good
stability
in
alkaline
electrolyte,
much
better
than
that
bi/monometallic
oxides
even
commercial
RuO
2
.
Energy & Environmental Science,
Год журнала:
2021,
Номер
14(4), С. 1722 - 1770
Опубликована: Янв. 1, 2021
A
tuned
electronic
structure
favors
the
electrocatalytic
water
splitting
reactionviaaccelerating
reaction
kinetics,
changing
rate-determining
step,
and
optimizing
adsorption
energy
for
intermediates;
this
is
achievedviaintentionally
incorporating
imperfections
into
crystal
lattices
of
electrocatalysts.
