Environmental Science & Technology,
Год журнала:
2021,
Номер
55(13), С. 9189 - 9198
Опубликована: Май 28, 2021
Many
reagents
as
electron
sacrificers
have
been
recently
investigated
to
induce
decomposition
of
permanganate
(KMnO4)
produce
highly
reactive
intermediate
Mn
species
toward
oxidation
organic
contaminants;
however,
this
strategy
meanwhile
causes
low
KMnO4
utilization
efficiency.
This
study
surprisingly
found
that
graphite
can
mediate
direct
transfer
from
organics
(e.g.,
sulfamethoxazole
(SMX))
KMnO4,
resulting
in
high
efficiency,
rather
than
reductive
sites
graphite-induced
conversion
species.
The
galvanic
process
(GOP)
and
comparative
experiments
different
contaminants
prove
the
KMnO4/graphite
system
mainly
extracts
electrons
via
a
one-electron
pathway
instead
two-electron
pathway.
More
importantly,
has
superior
reusability,
keep
long-lasting
reactivity,
efficiency
elevates
significantly
after
each
cycle
graphite.
transformation
SMX
includes
self-coupling,
hydroxylation,
oxidation,
hydrolytic
reaction.
work
will
improve
insights
into
electron-transfer
mechanism
unveil
advantages
efficient
KMnO4-based
technologies
environmental
remediation.
Environmental Science & Technology,
Год журнала:
2021,
Номер
56(1), С. 78 - 97
Опубликована: Дек. 21, 2021
Persulfate-based
nonradical
oxidation
processes
(PS-NOPs)
are
appealing
in
wastewater
purification
due
to
their
high
efficiency
and
selectivity
for
removing
trace
organic
contaminants
complicated
water
matrices.
In
this
review,
we
showcased
the
recent
progresses
of
state-of-the-art
strategies
electron-transfer
regimes
PS-NOPs,
including
design
metal
metal-free
heterogeneous
catalysts,
situ/operando
characterization/analytical
techniques,
insights
into
origins
mechanisms.
a
typical
process
(ETP),
persulfate
is
activated
by
catalyst
form
surface
complexes,
which
directly
or
indirectly
interact
with
target
pollutants
finalize
oxidation.
We
discussed
different
analytical
techniques
on
fundamentals
tactics
accurate
analysis
ETP.
Moreover,
demonstrated
challenges
proposed
future
research
ETP-based
systems,
such
as
computation-enabled
molecular-level
investigations,
rational
real-scenario
applications
environment.
Overall,
review
dedicates
sharpening
understanding
ETP
PS-NOPs
presenting
promising
remediation
technology
green
chemistry.
Environmental Science & Technology,
Год журнала:
2020,
Номер
54(10), С. 6438 - 6447
Опубликована: Апрель 17, 2020
Persulfates
activation
by
carbon
nanotubes
(CNT)
has
been
evidenced
as
nonradical
systems
for
oxidation
of
organic
pollutants.
Peroxymonosulfate
(PMS)
and
peroxydisulfate
(PDS)
possess
discrepant
atomic
structures
redox
potentials,
while
the
nature
their
distinct
behaviors
in
carbocatalytic
not
investigated.
Herein,
we
illustrated
that
roles
nitrogen
species
CNT-based
persulfate
are
intrinsically
different.
In
PMS
mediated
nitrogen-doped
CNT
(N-CNT),
surface
chemical
modification
(N-doping)
can
profoundly
promote
adsorption
quantity
PMS,
consequently
elevate
potential
derived
N-CNT–PMS*
complexes,
boost
efficiency
via
an
electron-transfer
regime.
contrast,
PDS
was
enhanced
upon
incorporating
N
into
due
to
limited
equilibrium
PDS,
leading
a
relatively
lower
oxidative
PDS/N-CNT
system
mediocre
degradation
rate.
However,
with
equivalent
on
N-CNT
at
low
quantity,
exhibited
stronger
oxidizing
capacity
than
PMS/N-CNT
because
intrinsic
higher
PMS.
The
rates
two
were
great
linearity
potentials
carbon–persulfate*
suggesting
shared
similar
mechanism.
Therefore,
this
study
provides
new
insights
heteroatom
doping
nanocarbons
persulfates
unveils
principles
rational
design
reaction-oriented
carbocatalysts
persulfate-based
advanced
processes.
Environmental Science & Technology,
Год журнала:
2020,
Номер
54(13), С. 8464 - 8472
Опубликована: Июнь 10, 2020
Nanocarbon-based
persulfate
oxidation
emerges
as
a
promising
technology
for
the
elimination
of
organic
micropollutants
(OMPs).
However,
nature
active
site
and
its
working
mechanism
remain
elusive,
impeding
developments
high-performance
oxidative
water
treatment
practice.
Here,
we
report
that
defect-rich
carbon
nanotubes
(CNTs)
exhibit
superior
activity
in
activation
peroxymonosulfate
(PMS)
OMP
oxidation.
Quantitative
structure-activity
relationship
studies
combined
with
theoretical
calculations
unveil
double-vacancy
defect
on
CNTs
may
be
intrinsic
site,
which
works
conductive
bridge
to
facilitate
potential
difference-dominated
electron
transfer
from
highest
occupied
molecular
orbital
OMPs
lowest
unoccupied
PMS.
Based
this
unique
mechanism,
established
CNTs@PMS
system
achieves
outstanding
selectivity
realizes
target-oriented
specific
complicated
aquatic
environment.
This
work
sheds
new
light
carbocatalysis
selective
develops
an
innovative
toward
remediation
practical
wastewater.
Environmental Science & Technology,
Год журнала:
2022,
Номер
56(16), С. 11635 - 11645
Опубликована: Июль 11, 2022
Single-atom
catalysts
(SACs)-based
peroxymonosulfate
(PMS)
systems
are
highly
selective
to
the
type
of
organic
pollutants
while
mechanisms
remain
ambiguous.
In
this
work,
we
carried
out
experimental
and
theoretical
investigations
reveal
origins
selectivity
radical
nonradical
pathways
in
a
designated
Co–N4–C/PMS
system.
Two
typical
[bisphenol
A
(BPA)
metronidazole
(MNZ)]
with
different
molecular
structures
were
employed
for
comparison.
We
found
that
oxidation
(SO4•–
HO•)
electron-transfer
pathway
(ETP)
co-existed
Pollutants
(e.g.,
MNZ)
high
redox
potential
degraded
primarily
by
free
radicals
rather
than
ETP,
oxidization
low-redox
BPA)
was
dominated
ETP
at
surface
region
Co–N4–C
which
overwhelmed
contributions
homogeneous
phase.
Intriguingly,
could
be
manipulated
PMS
loading,
simultaneously
increased
population
elevated
Co–N4–C-PMS*
complexes
ETP.
Findings
from
work
will
unravel
mysterious
behavior
SACs/PMS
micropollutants.
