Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Янв. 26, 2024
Abstract
The
selective
oxidative
dehydrogenation
of
ethane
(ODHE)
is
attracting
increasing
attention
as
a
method
for
ethylene
production.
Typically,
thermocatalysts
operating
at
high
temperatures
are
needed
C–H
activation
in
ethane.
In
this
study,
we
describe
low
temperature
(
<
140
°C)
photocatalytic
route
ODHE,
using
O
2
the
oxidant.
A
photocatalyst
containing
PdZn
intermetallic
nanoparticles
supported
on
ZnO
prepared,
affording
an
production
rate
46.4
mmol
g
–1
h
with
92.6%
selectivity
under
365
nm
irradiation.
When
employ
simulated
shale
gas
feed,
ODHE
system
achieves
nearly
20%
conversion
while
maintaining
about
87%.
robust
interface
between
and
support
plays
crucial
role
through
photo-assisted
Mars-van
Krevelen
mechanism,
followed
by
rapid
lattice
oxygen
replenishment
to
complete
reaction
cycle.
Our
findings
demonstrate
that
promising
alkane-to-alkene
conversions
mild
conditions.
Journal of the American Chemical Society,
Год журнала:
2022,
Номер
144(35), С. 15977 - 15987
Опубликована: Авг. 15, 2022
Photocatalytic
conversion
of
methane
to
value-added
products
under
mild
conditions,
which
represents
a
long
sought-after
goal
for
industrial
sustainable
production,
remains
extremely
challenging
afford
high
production
and
selectivity
using
cheap
catalysts.
Herein,
we
present
the
crystal
phase
engineering
commercially
available
anatase
TiO2
via
simple
thermal
annealing
optimize
structure-property
correlation.
A
biphase
catalyst
with
(90%)
rutile
(10%)
optimal
interface
concentration
exhibits
exceptional
performance
in
oxidation
formaldehyde
reaction
conditions
water
solvent,
oxygen
atmosphere,
full-spectrum
light
irradiation.
An
unprecedented
24.27
mmol
gcat-1
an
excellent
97.4%
toward
is
acquired
at
room
temperature
after
3
h
reaction.
Both
experimental
results
theoretical
calculations
disclose
that
lengthens
lifetime
photogenerated
carriers
favors
formation
intermediate
methanol
species,
thus
maximizing
efficiency
aerobic
formaldehyde.
More
importantly,
feasibility
scale-up
demonstrated
by
inventing
"pause-flow"
reactor.
This
work
opens
avenue
transformation
economical
way.
Journal of the American Chemical Society,
Год журнала:
2022,
Номер
144(27), С. 12357 - 12366
Опубликована: Июнь 28, 2022
The
huge
challenge
for
CH4
photooxidation
into
CH3OH
lies
in
the
activation
of
inert
C-H
bond
and
inhibition
overoxidation.
Herein,
we
design
two-dimensional
in-plane
Z-scheme
heterostructures
composed
two
different
metal
oxides,
with
efforts
to
polarize
symmetrical
molecules
strengthen
O-H
CH3OH.
As
a
prototype,
first
fabricate
ZnO/Fe2O3
porous
nanosheets,
where
high-resolution
transmission
electron
microscopy
situ
X-ray
photoelectron
spectroscopy
affirm
their
heterostructure.
In
Fourier
transform
infrared
spectra
paramagnetic
resonance
demonstrate
higher
amount
·CH3
radicals
relative
pristine
ZnO
which
density
functional
theory
calculations
validate
that
high
local
charge
accumulation
on
Fe
sites
lowers
adsorption
energy
from
0.14
0.06
eV.
Moreover,
charge-accumulated
polarity
through
transferring
electrons
O
atoms,
confirmed
by
increased
barrier
0.30
2.63
eV
*CH3O
formation,
inhibits
homolytic
cleavage
thus
suppresses
Accordingly,
selectivity
over
nanosheets
reaches
up
nearly
100%
an
activity
178.3
μmol-1
gcat-1,
outperforming
previously
reported
photocatalysts
without
adding
any
oxidants
under
room
temperature
ambient
pressure.
Carbon Energy,
Год журнала:
2021,
Номер
3(4), С. 519 - 540
Опубликована: Июль 22, 2021
Abstract
Conversion
of
methane
into
value‐added
chemicals
is
significance
for
utilization
and
industrial
demand
primary
chemical
products.
The
barrier
associated
with
the
nonpolar
structure
high
bond
energy
C–H
(4.57
eV)
makes
it
difficult
to
realize
conversion
activation
under
mild
conditions.
photothermal
synergetic
strategy
by
combining
photon
thermo
provides
an
advanced
philosophy
achieve
efficient
conversion.
In
this
review,
we
overview
current
pioneering
studies
indirect
present
direct
way
photocatalysis
thermocatalysis
provide
a
fundamental
understanding
activation.
Finally,
end
review
discussion
on
remaining
challenges
perspectives
over
single‐atom
catalysts
via
strategy.
ACS Nano,
Год журнала:
2022,
Номер
16(6), С. 8557 - 8618
Опубликована: Май 31, 2022
Direct
conversion
of
methane
(CH4)
to
C1–2
liquid
oxygenates
is
a
captivating
approach
lock
carbons
in
transportable
value-added
chemicals,
while
reducing
global
warming.
Existing
approaches
utilizing
the
transformation
CH4
fuel
via
tandemized
steam
reforming
and
Fischer–Tropsch
synthesis
are
energy
capital
intensive.
Chemocatalytic
partial
oxidation
remains
challenging
due
negligible
electron
affinity,
poor
C–H
bond
polarizability,
high
activation
barrier.
Transition-metal
stoichiometric
catalysts
harsh
oxidants
reaction
conditions
perform
poorly
with
randomized
product
distribution.
Paradoxically,
which
active
enough
break
also
promote
overoxidation,
resulting
CO2
generation
reduced
carbon
balance.
Developing
can
bonds
selectively
make
useful
chemicals
at
mild
vital
commercialization.
Single
atom
(SACs)
specifically
coordinated
metal
centers
on
support
have
displayed
intrigued
reactivity
selectivity
for
oxidation.
SACs
significantly
reduce
induced
electrostatic
polarization
facilitate
accelerated
rate
low
temperature.
The
distinct
metal–support
interaction
stabilize
intermediate
prevent
overoxidation
products.
present
review
accounts
recent
progress
field
selective
oxygenates.
chemical
nature
catalytic
sites,
effects
interaction,
stabilization
species
minimize
thoroughly
discussed
forward-looking
perspective
improve
performance.
Nature Communications,
Год журнала:
2023,
Номер
14(1)
Опубликована: Май 10, 2023
Direct
solar-driven
methane
(CH4)
reforming
is
highly
desirable
but
challenging,
particularly
to
achieve
a
value-added
product
with
high
selectivity.
Here,
we
identify
synergistic
ensemble
effect
of
atomically
dispersed
copper
(Cu)
species
and
partially
reduced
tungsten
(Wδ+),
stabilised
over
an
oxygen-vacancy-rich
WO3,
which
enables
exceptional
photocatalytic
CH4
conversion
formaldehyde
(HCHO)
under
visible
light,
leading
nearly
100%
selectivity,
very
yield
4979.0
μmol·g-1
within
2
h,
the
normalised
mass
activity
8.5
×
106
μmol·g-1Cu·h-1
HCHO
at
ambient
temperature.
In-situ
EPR
XPS
analyses
indicate
that
Cu
serve
as
electron
acceptor,
promoting
photo-induced
transfer
from
conduction
band
O2,
generating
reactive
•OOH
radicals.
In
parallel,
adjacent
Wδ+
act
hole
acceptor
preferred
adsorption
activation
site
H2O
produce
hydroxyl
radicals
(•OH),
thus
activate
methyl
(•CH3).
The
synergy
dual
active
sites
boosts
overall
efficiency
selectivity
process.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(23)
Опубликована: Апрель 7, 2023
Abstract
Methane
conversion
to
higher
hydrocarbons
requires
harsh
reaction
conditions
due
high
energy
barriers
associated
with
C−H
bond
activation.
Herein,
we
report
a
systematic
investigation
of
photocatalytic
oxidative
coupling
methane
(OCM)
over
transition‐metal‐loaded
ZnO
photocatalysts.
A
1
wt
%
Au/ZnO
delivered
remarkable
C
2
‐C
4
hydrocarbon
production
rate
683
μmol
g
−1
h
(83
selectivity)
under
light
irradiation
excellent
photostability
two
days.
The
metal
type
and
its
interaction
strongly
influence
the
selectivity
toward
C−C
products.
Photogenerated
Zn
+
‐O
−
sites
enable
CH
activation
methyl
intermediates
(*CH
3
)
migrating
onto
adjacent
nanoparticles.
nature
*CH
‐metal
controls
OCM
In
case
Au,
strong
d‐σ
orbital
hybridization
reduces
metal‐C−H
angles
steric
hindrance,
thereby
enabling
efficient
coupling.
Findings
indicate
center
may
be
suitable
descriptor
for
predicting
product
during
metal/ZnO