Environmental Science & Technology,
Journal Year:
2022,
Volume and Issue:
56(12), P. 7924 - 7934
Published: May 19, 2022
Oxygen
vacancies
play
a
vital
role
in
the
catalytic
activity
of
layered
double
hydroxide
(LDH)
catalysts
wastewater
treatment.
However,
mechanism
oxygen
vacancy-mediated
LDH-activated
to
produce
reactive
species
(ROS)
still
lacks
reasonable
explanation.
In
this
work,
tartrate-modified
CuCoFe-LDH
(CuCoFe/Tar-LDH)
with
abundant
was
designed,
which
can
efficiently
degrade
nitrobenzene
(NB)
under
room
conditions.
The
technical
energy
consumption
is
0.011
kW
h
L–1.
According
characterization
and
calculation
results,
it
proposed
that
are
formed
because
deficiency
caused
by
reduction
between
metal
ion
oxygen,
transitions
lower
state.
Compared
CuCoFe-LDH,
vacancy
formation
CuCoFe/Tar-LDH
decreased
from
1.98
1.13
eV.
O2
bond
length
adsorbed
on
1.27
Å,
close
theoretical
superoxide
radicals
(•O2–)
(1.26
Å).
Radical
trapping
experiments
electron
spin-resonance
spectroscopy
spectrum
prove
•O2–
an
important
precursor
•OH.
This
work
dedicated
in-depth
exploration
catalyst
activation
for
molecular
conversion
relationship
ROS.
Angewandte Chemie International Edition,
Journal Year:
2021,
Volume and Issue:
60(40), P. 21751 - 21755
Published: Aug. 4, 2021
Abstract
Singlet
oxygen
(
1
O
2
)
is
an
excellent
active
species
for
the
selective
degradation
of
organic
pollutions.
However,
it
difficult
to
achieve
high
efficiency
and
selectivity
generation
.
In
this
work,
we
develop
a
graphitic
carbon
nitride
supported
Fe
single‐atoms
catalyst
(Fe
/CN)
containing
highly
uniform
Fe‐N
4
sites
with
loading
11.2
wt
%.
The
/CN
achieves
100
%
by
activating
peroxymonosulfate
(PMS),
which
shows
ultrahigh
p‐chlorophenol
efficiency.
Density
functional
theory
calculations
results
demonstrate
that
in
contrast
Co
Ni
single‐atom
sites,
adsorb
terminal
PMS,
can
facilitate
oxidization
PMS
form
SO
5
.−
,
thereafter
efficiently
generate
selectivity.
addition,
exhibits
strong
resistance
inorganic
ions,
natural
matter,
pH
value
during
pollutants
presence
PMS.
This
work
develops
novel
production
efficient
pollutants.
Environmental Science & Technology,
Journal Year:
2021,
Volume and Issue:
55(22), P. 15400 - 15411
Published: Nov. 5, 2021
Ubiquitous
oxygen
vacancies
(Vo)
existing
in
metallic
compounds
can
activate
peroxymonosulfate
(PMS)
for
water
treatment.
However,
under
environmental
conditions,
especially
oxygenated
surroundings,
the
interactions
between
Vo
and
PMS
as
well
organics
degradation
mechanism
are
still
ambiguous.
In
this
study,
we
provide
a
novel
insight
into
activation
over
Vo-containing
Fe–Co
layered
double
hydroxide
(LDH).
Experimental
results
show
that
Vo/PMS
is
capable
of
selective
via
single-electron-transfer
nonradical
pathway.
Moreover,
O2
firstly
demonstrated
most
critical
trigger
system.
Mechanistic
studies
reveal
that,
with
abundant
electrons
confined
vacant
electron
orbitals
Vo,
thermodynamically
enabled
to
capture
from
form
O2•–
imprinting
effect
start
process.
Simultaneously,
becomes
electron-deficient
withdraws
sustain
electrostatic
balance
achieve
(32%
Bisphenol
A
without
PMS).
Different
conventional
activation,
collaboration
kinetics
thermodynamics,
endowed
ability
donate
reductant
other
than
an
oxidant
1O2.
case,
1O2
act
indispensable
intermediate
species
accelerate
circulation
(as
high
14.3
mg/L)
micro
area
around
promote
nano-confinement
electron-recycling
process
67%
improvement
degradation.
This
study
provides
brand-new
perspective
natural
environments.
Environmental Science & Technology,
Journal Year:
2023,
Volume and Issue:
57(33), P. 12153 - 12179
Published: Aug. 3, 2023
Urbanization
and
industrialization
have
exerted
significant
adverse
effects
on
water
quality,
resulting
in
a
growing
need
for
reliable
eco-friendly
treatment
technologies.
Persulfate
(PS)-based
advanced
oxidation
processes
(AOPs)
are
emerging
as
viable
technologies
to
treat
challenging
industrial
wastewaters
or
remediate
groundwater
impacted
by
hazardous
wastes.
While
the
generated
reactive
species
can
degrade
variety
of
priority
organic
contaminants
through
radical
nonradical
pathways,
there
is
lack
systematic
in-depth
comparison
these
pathways
practical
implementation
different
scenarios.
Our
comparative
analysis
reaction
rate
constants
vs.
indicates
that
radical-based
AOPs
may
achieve
high
removal
efficiency
with
relatively
short
contact
time.
Nonradical
feature
advantages
minimal
matrix
interference
complex
wastewater
treatments.
(e.g.,
singlet
oxygen,
high-valent
metals,
surface
activated
PS)
preferentially
react
bearing
electron-donating
groups,
allowing
enhancement
degradation
known
target
contaminants.
For
byproduct
formation,
analytical
limitations
computational
chemistry
applications
also
considered.
Finally,
we
propose
holistically
estimated
electrical
energy
per
order
(EE/O)
parameter
show
significantly
higher
requirements
pathways.
Overall,
critical
comparisons
help
prioritize
basic
research
PS-based
inform
merits
system-specific
applications.
Environmental Science & Technology,
Journal Year:
2021,
Volume and Issue:
55(23), P. 16078 - 16087
Published: Oct. 11, 2021
Graphitized
nanodiamonds
(ND)
exhibit
outstanding
capability
in
activating
peroxymonosulfate
(PMS)
for
the
removal
of
aqueous
organic
micropollutants
(OMPs).
However,
controversial
observation
and
interpretation
regarding
effect
graphitization
degree
on
ND's
activity
role
singlet
oxygen
(1O2)
OMP
degradation
need
to
be
clarified.
Herein,
we
investigated
graphitized
ND-mediated
PMS
activation.
Experiments
show
that
ND
increases
first
then
decreases
with
monotonically
increased
degree.
Further
experimental
theoretical
studies
unveil
intensified
surface
alters
mechanism
from
oxygenation
an
electron-transfer
pathway.
Moreover,
time,
applied
a
self-constructed,
time-resolved
phosphorescence
detection
system
provide
direct
evidence
1O2
production
PMS-based
system.
This
work
not
only
elucidates
degree-dependent
activation
but
also
provides
reliable
situ
analysis
future
studies.
Environmental Science & Technology,
Journal Year:
2022,
Volume and Issue:
56(15), P. 10710 - 10720
Published: May 12, 2022
Efficient
degradation
of
organic
pollutants
by
oxidative
radicals
is
challenging
in
the
complex
soil
environment
because
invalid
consumption
nontarget
background
substances
and
generation
secondary
halogenated
pollutants.
Nonradical-based
oxidation
a
promising
pollutant
removal
method
due
to
its
high
selectivity
environmental
adaptability.
Herein,
biochar-supported
sheetlike
CuO
(e-CuO@BC)
was
developed,
which
exhibited
efficient
activation
peroxydisulfate
(PDS)
via
nonradical
pathways.
The
mechanisms
were
identified
as
(i)
formation
surface-bonding
active
complexes
an
outer-sphere
interaction
between
e-CuO@BC
PDS
(ii)
continuous
1O2
cycling
Cu(I)/Cu(II)
redox
couple.
In
addition,
primarily
occurred
at
crystal
facet
(001)
e-CuO
occupied
Cu
atoms
well
facilitated
Cu–O–C
bond,
induced
electron-rich
centers
around
CuO.
Two
species
from
activation,
including
1O2,
showed
highly
selective
toward
Moreover,
mineralization
effective
inhibition
on
toxic
byproducts
(i.e.,
organics)
indicated
intermediate
final
products.
This
study
provides
comprehensive
understanding
heterogeneous
process
PS
catalyst
for
removal.
