Proceedings of the National Academy of Sciences,
Год журнала:
2024,
Номер
121(51)
Опубликована: Дек. 13, 2024
Biomass-burning
organic
aerosol(s)
(BBOA)
are
rich
in
brown
carbon,
which
significantly
absorbs
solar
irradiation
and
potentially
accelerates
global
warming.
Despite
its
importance,
the
multiphase
photochemistry
of
BBOA
after
light
absorption
remains
poorly
understood
due
to
challenges
determining
oxidant
concentrations
reaction
kinetics
within
aerosol
particles.
In
this
study,
we
explored
photochemical
reactivity
particles
S(IV)
oxidation
sulfate.
We
found
that
sulfate
formation
under
is
predominantly
driven
by
photosensitization
involving
triplet
excited
states
(
3
*
)
instead
iron,
nitrate,
photochemistry.
Rates
three
orders
magnitude
higher
than
those
observed
bulk
solution,
primarily
fast
interfacial
reactions.
Our
results
highlight
chemistry
can
greatly
contribute
sulfate,
as
an
example
secondary
pollutants.
Photosensitization
will
likely
become
increasingly
crucial
intensified
wildfires.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(2), С. 1467 - 1475
Опубликована: Янв. 8, 2024
We
present
a
novel
mechanism
for
the
formation
of
photocatalytic
oxidants
in
deliquescent
NaCl
particles,
which
can
greatly
promote
multiphase
photo-oxidation
SO2
to
produce
sulfate.
The
photoexcitation
[Cl––H3O+–O2]
complex
leads
generation
Cl
and
OH
radicals,
is
key
reason
enhancing
aqueous-phase
oxidation
accelerating
oxidation.
mass
normalization
rate
sulfate
production
from
photoreaction
on
droplets
could
be
estimated
0.80
×
10–4
μg·h–1
at
72%
RH
1.33
81%
RH,
equivalent
known
O3
liquid-phase
mechanism.
Our
findings
highlight
significance
particles
as
non-negligible
source
coastal
areas.
Furthermore,
this
study
underscores
importance
Cl–
photochemistry
atmosphere.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(10), С. 6580 - 6590
Опубликована: Март 1, 2024
The
multiphase
oxidation
of
sulfur
dioxide
(SO2)
to
form
sulfate
is
a
complex
and
important
process
in
the
atmosphere.
While
conventional
photosensitized
reaction
mainly
explored
bulk
medium
reported
be
one
drivers
trigger
atmospheric
production,
how
this
scheme
functionalizes
at
air–water
interface
(AWI)
aerosol
remains
an
open
question.
Herein,
employing
advanced
size-controllable
microdroplet-printing
device,
surface-enhanced
Raman
scattering
(SERS)
analysis,
nanosecond
transient
adsorption
spectrometer,
molecular
level
theoretical
calculations,
we
revealed
previously
overlooked
interfacial
role
SO2
humic-like
substance
(HULIS)
aerosol,
where
3–4
orders
magnitude
increase
formation
rate
was
speculated
cloud
relevant-sized
particles
relative
bulk-phase
medium.
rapid
battery
reactive
oxygen
species
(ROS)
comes
from
accelerated
electron
transfer
AWI,
excited
triplet
state
HULIS
(3HULIS*)
incomplete
solvent
cage
can
readily
capture
electrons
HSO3–
way
that
more
efficient
than
fully
blocked
by
water
molecules.
This
phenomenon
could
explained
significantly
reduced
desolvation
energy
barrier
required
for
reagents
residing
AWI
region
with
shell.
Environmental Science & Technology,
Год журнала:
2024,
Номер
58(18), С. 7924 - 7936
Опубликована: Апрель 23, 2024
Aromatic
carbonyls
have
been
mainly
probed
as
photosensitizers
for
aqueous
secondary
organic
aerosol
(aqSOA)
and
light-absorbing
(i.e.,
brown
carbon
or
BrC)
formation,
but
due
to
their
nature,
they
can
also
undergo
oxidation
form
aqSOA
BrC.
However,
photochemical
transformations
of
aromatic
carbonyl
photosensitizers,
particularly
in
multicomponent
systems,
are
understudied.
This
study
explored
formation
from
the
irradiation
mixed
single
systems
under
cloud/fog
conditions.
Mixed
consisting
phenolic
only
(VL
+
ActSyr
SyrAld:
vanillin
[VL]
acetosyringone
[ActSyr]
syringaldehyde
[SyrAld])
another
composed
both
nonphenolic
(DMB
3,4-dimethoxybenzaldehyde
[DMB],
a
carbonyl,
SyrAld)
were
compared
VL
(VL*)
DMB
(DMB*),
respectively.
In
shorter
lifetimes
indicate
diminished
capacity
trigger
other
compounds
(e.g.,
guaiacol
[GUA],
noncarbonyl
phenol).
contrast
slow
decay
minimal
photoenhancement
DMB*,
rapid
photodegradation
significant
VL*
efficient
direct
photosensitized
self-photosensitization).
Relative
increased
oxidant
availability
promoted
functionalization
SyrAld
accelerated
conversion
early
generation
SyrAld.
Moreover,
oxidizable
substrates
countered
by
stronger
oxidative
limited
contribution
light
absorption.
suggests
weaker
radiative
effect
BrC
photosensitizer
than
systems.
Furthermore,
more
oxygenated
oxidized
was
observed
with
increasing
complexity
reaction
<
GUA).
work
offers
new
insights
into
emphasizing
dual
role
sources
substrates.
ACS ES&T Air,
Год журнала:
2024,
Номер
1(2), С. 92 - 102
Опубликована: Янв. 23, 2024
Numerous
studies
have
demonstrated
that
organic
photosensitizers
from
biomass
burning
can
generate
oxidants
to
effectively
convert
inorganic
and
precursors
into
secondary
aerosols.
Particulate
chloride
ions
be
internally
mixed
with
in
particles.
In
this
study,
we
investigate
the
impact
of
interaction
chlorine
chemistry
photosensitization
on
oxidative
potential
aerosols
by
utilizing
SO2
oxidation
form
sulfate
as
an
indicator.
Mixed
particles
glyoxal
its
reaction
products
ammonia
imidazole-2-carboxaldehyde
(IC)
were
studied.
Premixed
NH4Cl
+
a
4–5
times
higher
formation
rate
than
premixed
NaCl
glyoxal,
particularly
at
low
relative
humidity,
suggesting
role
photosensitization.
Furthermore,
addition
IC
resulted
∼73-fold
increase
production
compared
alone.
No
noticeable
was
observed
presence
alone,
likely
due
high
particle
acidity
study
(i.e.,
pH
=
2).
The
kinetic
analysis
these
results
yields
constant
triplet
state
IC,
3IC*,
∼3
orders
magnitude
previously
reported
values
bulk
solution.
These
findings
underscore
significance
synergetic
effect
enhancing
atmospheric
capacity.
ACS ES&T Air,
Год журнала:
2024,
Номер
1(11), С. 1333 - 1351
Опубликована: Окт. 10, 2024
Brown
carbons
(BrCs)
play
a
pivotal
role
in
the
light
absorption
by
aerosol
particulates
exerting
positive
radiative
forcing
effect
that
contributes
to
global
warming.
Beyond
impacts
on
balance,
some
BrCs,
as
photosensitizers,
can
generate
reactive
triplet-state
molecules
toward
various
atmospheric
upon
photoexcitation.
The
significance
of
photosensitization
has
been
increasingly
recognized,
particularly
context
escalated
wildfire
incidents
emit
substantial
BrCs.
We
focus
complex
discussing
current
challenges,
including
(1)
diverse
reactivities
photosensitizer
mixture
particles,
(2)
methodologies
for
investigating
processes,
(3)
driving
factors
photosensitization,
and
(4)
typical
pathways
mechanisms
photosensitized
reactions.
Lastly,
we
advise
future
research
refined
parametrization
triplet
singlet
oxygen
concentrations,
alongside
their
reactivities.
Atmospheric chemistry and physics,
Год журнала:
2025,
Номер
25(1), С. 425 - 439
Опубликована: Янв. 13, 2025
Abstract.
Discrepancies
persist
between
modeled
simulations
and
measured
sulfate
concentrations
in
the
marine
boundary
layer,
especially
when
air
is
influenced
by
biomass
burning
plumes.
However,
there
has
been
a
notable
dearth
of
research
conducted
on
interactions
sea-salt
aerosol
plumes,
impeding
comprehensive
understanding
formation.
This
work
studied
formation
mixing
real
(BB)
extracts
NaCl,
mimicking
internal
mixtures
BB
particles.
BB–NaCl
particles
had
significantly
higher
rate
than
incense
(IS)–NaCl
For
fresh
particles,
followed
trend
corn
straw
(CS)–NaCl
>
rice
(RS)–NaCl
wheat
(WS)–NaCl
IS–NaCl.
The
filter
sample
aging
was
achieved
exposure
to
OH•
generated
from
UV
irradiation.
After
aging,
RS–NaCl
exhibited
highest
enhancement
rates
among
all
due
RS
NaCl.
Bulk
aqueous
experiments
spiked
with
NaCl
using
model
photosensitizers
(PSs)
nitrogen-containing
organic
compounds
(NOCs),
pyrazine
(CHN),
4-nitrocatechol
(CHON)
revealed
positive
effects
chloride
PS–CHON
system
negative
PS–CHN
Our
suggests
that
reaching
or
near
coastal
areas
can
affect
via
photosensitizer-mediated
reactions,
potentially
exacerbating
pollution.
