Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(43)
Опубликована: Сен. 5, 2023
Singlet
oxygen
(1
O2
)
is
an
excellent
reactive
species
(ROSs)
for
the
selective
conversion
of
organic
matter,
especially
in
advanced
oxidation
processes
(AOPs).
However,
due
to
huge
dilemma
synthesizing
single-site
type
catalysts,
control
and
regulation
1
generation
AOPs
still
challenging
underlying
mechanism
remains
largely
obscure.
Here,
taking
advantage
well-defined
flexibly
tunable
sites
covalent
frameworks
(COFs),
we
report
first
achievement
precisely
regulating
ROSs
peroxymonosulfate
(PMS)-based
by
site
engineering
COFs.
Remarkably,
COFs
with
bipyridine
units
(BPY-COFs)
facilitate
PMS
activation
via
a
nonradical
pathway
100
%
,
whereas
biphenyl-based
(BPD-COFs)
almost
identical
structures
activate
produce
radicals
(⋅OH
SO4.-
).
The
BPY-COFs/PMS
system
delivers
boosted
performance
degradation
target
pollutants
from
water,
which
ca.
9.4
times
that
its
BPD-COFs
counterpart,
surpassing
most
reported
PMS-based
systems.
Mechanism
analysis
indicated
highly
electronegative
pyridine-N
atoms
on
BPY-COFs
provide
extra
adsorb
terminal
H
PMS,
resulting
simultaneous
adsorption
O
one
pyridine
ring,
facilitates
cleavage
S-O
bond
generate
.
Nature Communications,
Год журнала:
2023,
Номер
14(1)
Опубликована: Май 19, 2023
Abstract
There
is
an
urgent
need
to
develop
effective
and
sustainable
solutions
reduce
water
pollution.
Heterogeneous
Fenton-like
catalysts
are
frequently
used
eliminate
contaminants
from
water.
However,
the
applicability
of
these
limited
due
low
availability
reactive
species
(RS).
Herein,
nanoconfinement
strategy
was
applied
encapsulate
short-lived
RS
at
nanoscale
boost
utilization
efficiency
in
reactions.
The
nanoconfined
catalyst
fabricated
by
assembling
Co
3
O
4
nanoparticles
carbon
nanotube
nanochannels
achieve
exceptional
reaction
rate
excellent
selectivity.
Experiments
collectively
suggested
that
degradation
attributed
singlet
oxygen
(
1
2
).
Density
functional
theory
calculations
demonstrated
space
contributes
quantum
mutation
alters
transition
state
lower
activation
energy
barriers.
Simulation
results
revealed
enrichment
contaminant
on
reduced
migration
distance
enhanced
.
synergy
between
shell
layer
core-shell
structure
further
improved
selectivity
towards
oxidation
real
waters.
expected
provide
a
viable
for
pollution
control.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
61(29)
Опубликована: Май 6, 2022
Abstract
Simultaneous
regulation
of
the
coordination
environment
single‐atom
catalysts
(SACs)
and
engineering
architectures
with
efficient
exposed
active
sites
are
strategies
for
boosting
peroxymonosulfate
(PMS)
activation.
We
isolated
cobalt
atoms
dual
nitrogen
oxygen
(Co−N
3
O
1
)
on
oxygen‐doped
tubular
carbon
nitride
(TCN)
by
pyrolyzing
a
hydrogen‐bonded
cyanuric
acid
melamine–cobalt
acetate
precursor.
The
theoretically
constructed
Co−N
moiety
TCN
exhibited
an
impressive
mass
activity
7.61×10
5
min
−1
mol
high
2
selectivity.
Theoretical
calculations
revealed
that
single
occupied
environment,
PMS
adsorption
was
promoted
energy
barriers
reduced
key
*O
intermediate
produced
.
were
attached
to
widely
used
poly(vinylidene
fluoride)
microfiltration
membrane
deliver
antibiotic
wastewater
treatment
system
97.5
%
ciprofloxacin
rejection
over
10
hours,
thereby
revealing
suitability
industrial
applications.
Environmental Science & Technology,
Год журнала:
2022,
Номер
56(12), С. 8833 - 8843
Опубликована: Май 26, 2022
Single
oxygen-based
advanced
oxidation
processes
(1O2-AOPs)
exhibit
great
prospects
in
selective
degradation
of
organic
pollutants.
However,
efficient
production
1O2
via
tailored
design
catalysts
to
achieve
contaminants
remains
challenging.
Herein,
we
develop
a
simple
strategy
regulate
the
components
and
coordination
Co–N–C
at
atomic
level
by
adjusting
Zn/Co
ratio
bimetallic
zeolitic
imidazolate
frameworks
(ZnxCo1-ZIFs).
Zn4Co1–C
demonstrates
98%
removal
phenol
mixed
phenol/benzoic
acid
(phenol/BA)
solutions.
Density
functional
theory
calculations
experiments
reveal
that
more
active
CoN4
sites
are
generated
Zn4Co1–C,
which
beneficial
peroxymonosulfate
activation
generate
1O2.
Furthermore,
correlation
between
origin
selectivity
well-defined
is
systematically
investigated
electron
paramagnetic
resonance
test
quenching
experiments.
This
work
may
provide
novel
insights
into
target
pollutants
complicated
water
matrix.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
61(33)
Опубликована: Июнь 20, 2022
Abstract
Understanding
the
site
interaction
nature
of
single‐atom
catalysts
(SACs),
especially
densely
populated
SACs,
is
vital
for
their
application
to
various
catalytic
reactions.
Herein,
we
report
a
distance
effect,
which
emphasizes
how
well
adjacent
copper
atoms
(denoted
as
d
Cu1−Cu1
)
matches
with
reactant
peroxydisulfate
(PDS)
molecular
size
determine
Fenton‐like
reaction
reactivity
on
carbon‐supported
SACs.
The
optimized
in
range
5–6
Å,
PDS,
endows
catalyst
nearly
two
times
higher
turnover
frequency
than
that
beyond
this
range,
accordingly
achieving
record‐breaking
kinetics
oxidation
emerging
organic
contaminants.
Further
studies
suggest
effect
originates
from
alteration
PDS
adsorption
dual‐site
structure
Cu
1
−Cu
sites
when
falls
within
significantly
enhancing
interfacial
charge
transfer
and
consequently
resulting
most
efficient
activation
so
far.
Environmental Science & Technology,
Год журнала:
2022,
Номер
56(12), С. 8984 - 8992
Опубликована: Май 31, 2022
In
persulfate
activation
by
copper-based
catalysts,
high-valent
copper
(Cu(III))
is
an
overlooked
reactive
intermediate
that
contributes
to
efficient
utilization
and
organic
pollutant
removal.
However,
the
mechanisms
underlying
heterogeneous
enhanced
are
not
fully
understood.
Here,
oxide
(CuO)
nanosheets
(synthesized
with
a
facile
precipitation
method)
exhibited
high
catalytic
activity
for
peroxymonosulfate
(PMS)
100%
4-chlorophenol
(4-CP)
degradation
within
3
min.
Evidence
critical
role
of
surface-associated
Cu(III)
on
PMS
4-CP
over
wide
pH
range
(pH
3-10)
was
obtained
using
in
situ
Raman
spectroscopy,
electron
paramagnetic
resonance,
quenching
tests.
directly
oxidized
other
phenolic
pollutants,
rate
constants
inversely
proportional
their
ionization
potentials.
preferentially
oxidizes
rather
than
react
two
molecules
generate
one
molecule
1O2,
thus
minimizing
this
less
pathway.
Accordingly,
much
higher
efficiency
(77%
electrons
accepted
ascribed
mineralization)
CuO/PMS
radical
pathway-dominated
Co3O4/PMS
system
(27%)
or
1O2
α-MnO2/PMS
(26%).
Overall,
these
results
highlight
potential
benefits
via
oxidation
offer
mechanistic
insight
into
ultrahigh
Advanced Functional Materials,
Год журнала:
2022,
Номер
32(38)
Опубликована: Июль 7, 2022
Abstract
Single‐atom
catalysts
(SACs)
are
widely
investigated
in
Fenton‐like
reactions
for
environmental
remediation,
wherein
their
catalytic
performance
can
be
further
improved
by
coordination
structure
modulation,
but
the
relevant
report
is
rare.
Herein,
a
series
of
atomically
dispersed
cobalt
with
diverse
numbers
(denoted
as
CoN
x
,
represents
nitrogen
number)
synthesized
and
peroxymonosulfate
(PMS)
conversion
explored.
The
specific
activity
found
to
dependent
on
number
single
atomic
Co
sites,
where
lowest‐coordinated
2
catalyst
exhibits
highest
PMS
activation,
followed
under‐coordinated
3
normal
4
.
Experimental
theoretical
results
reveal
that
reducing
increase
electron
density
atom
which
governs
catalysts.
Specifically,
entire
Co–pyridinic
NC
motif
serves
active
centers
conversion,
atom,
pyridinic
N‐bonded
C
atoms
along
vacancy
neighboring
unsaturated
N
moiety
account
reduction
oxidation
toward
radical
singlet
oxygen
(
1
O
)
generation,
respectively.
These
findings
provide
useful
avenue
regulation
SACs
applications.
Proceedings of the National Academy of Sciences,
Год журнала:
2023,
Номер
120(16)
Опубликована: Апрель 11, 2023
The
high-valent
cobalt-oxo
species
(Co(IV)=O)
is
being
increasingly
investigated
for
water
purification
because
of
its
high
redox
potential,
long
half-life,
and
antiinterference
properties.
However,
generation
Co(IV)=O
inefficient
unsustainable.
Here,
a
cobalt-single-atom
catalyst
with
N/O
dual
coordination
was
synthesized
by
O-doping
engineering.
O-doped
(Co-OCN)
greatly
activated
peroxymonosulfate
(PMS)
achieved
pollutant
degradation
kinetic
constant
73.12
min-1
g-2,
which
4.9
times
higher
than
that
Co-CN
(catalyst
without
O-doping)
those
most
reported
single-atom
catalytic
PMS
systems.
Co-OCN/PMS
realized
dominant
oxidation
pollutants
increasing
the
steady-state
concentration
(1.03
×
10-10
M)
5.9
compared
Co-CN/PMS.
A
competitive
kinetics
calculation
showed
contribution
to
micropollutant
97.5%
during
process.
Density
functional
theory
calculations
influenced
charge
density
(increased
Bader
transfer
from
0.68
0.85
e),
optimized
electron
distribution
Co
center
d-band
-1.14
-1.06
eV),
enhanced
adsorption
energy
-2.46
-3.03
eV,
lowered
barrier
key
reaction
intermediate
(*O*H2O)
formation
1.12
0.98
eV.
Co-OCN
fabricated
on
carbon
felt
flow-through
device,
continuous
efficient
removal
micropollutants
(degradation
efficiency
>85%
after
36
h
operation).
This
study
provides
new
protocol
activation
elimination
through
heteroatom-doping
metal-oxo
purification.
Advanced Materials,
Год журнала:
2022,
Номер
34(12)
Опубликована: Янв. 11, 2022
Rational
exploration
of
efficient,
inexpensive,
and
robust
electrocatalysts
is
critical
for
the
efficient
water
splitting.
Conjugated
conductive
metal-organic
frameworks
(cMOFs)
with
multicomponent
layered
double
hydroxides
(LDHs)
to
construct
bifunctional
heterostructure
catalysts
are
considered
as
an
but
complicated
strategy.
Here,
fabrication
a
cMOF/LDH
hetero-nanotree
array
catalyst
(CoNiRu-NT)
coupled
monodispersed
ruthenium
(Ru)
sites
via
controllable
grafted-growth
strategy
reported.
Rich-amino
hexaiminotriphenylene
linkers
coordinate
LDH
nanotrunk
form
cMOF
nanobranches,
providing
numerous
anchoring
precisely
confine
stabilize
RuN4
sites.
Moreover,
reduced
Ru
moieties
facilitate
H2
O
adsorption
dissociation,
heterointerface
between
further
modifies
chemical
electronic
structures.
Optimized
CoNiRu-NT
displays
significant
increase
in
electrochemical
water-splitting
properties
alkaline
media,
affording
low
overpotentials
22
mV
at
10
mA
cm-2
255
20
hydrogen
evolution
reaction
oxygen
reaction,
respectively.
In
actual
system,
drives
overall
splitting
cell
voltage
1.47
V
reach
.
This
performance
comparable
that
pure
noble-metal-based
materials
superior
most
reported
MOF-based
catalysts.