Angewandte Chemie International Edition,
Journal Year:
2022,
Volume and Issue:
62(12)
Published: Dec. 29, 2022
Abstract
Designing
polymeric
photocatalysts
at
the
molecular
level
to
modulate
photogenerated
charge
behavior
is
a
promising
and
challenging
strategy
for
efficient
hydrogen
peroxide
(H
2
O
)
photosynthesis.
Here,
we
introduce
electron‐deficient
1,4‐dihydroxyanthraquinone
(DHAQ)
into
framework
of
resorcinol‐formaldehyde
(RF)
resin,
which
modulates
donor/acceptor
ratio
from
perspective
design
promoting
separation.
Interestingly,
H
can
be
produced
via
oxygen
reduction
water
oxidation
pathways,
verified
by
isotopic
labeling
in
situ
characterization
techniques.
Density
functional
theory
(DFT)
calculations
elucidate
that
DHAQ
reduce
energy
barrier
production.
RF‐DHAQ
exhibits
excellent
overall
photosynthesis
with
solar‐to‐chemical
conversion
(SCC)
efficiency
exceeding
1.2
%.
This
work
opens
new
avenue
high‐efficiency
artificial
Journal of the American Chemical Society,
Journal Year:
2022,
Volume and Issue:
144(22), P. 9902 - 9909
Published: May 30, 2022
A
high-throughput
sonochemical
synthesis
and
testing
strategy
was
developed
to
discover
covalent
organic
frameworks
(COFs)
for
photocatalysis.
In
total,
76
conjugated
polymers
were
synthesized,
including
60
crystalline
COFs
of
which
18
previously
unreported.
These
then
screened
photocatalytic
hydrogen
peroxide
(H2O2)
production
using
water
oxygen.
One
these
COFs,
sonoCOF-F2,
found
be
an
excellent
photocatalyst
H2O2
even
in
the
absence
sacrificial
donors.
However,
after
long-term
tests
(96
h),
imine
sonoCOF-F2
transformed
into
amide-linked
COF
with
reduced
crystallinity
loss
electronic
conjugation,
decreasing
activity.
When
benzyl
alcohol
introduced
form
a
two-phase
catalytic
system,
photostability
greatly
enhanced,
leading
stable
at
least
1
week.
Journal of the American Chemical Society,
Journal Year:
2022,
Volume and Issue:
144(46), P. 21328 - 21336
Published: Nov. 9, 2022
Artificial
photosynthesis
of
H2O2
from
O2
reduction
provides
an
energy-saving,
safe,
and
green
approach.
However,
it
is
still
critical
to
develop
highly
active
selective
2e–
oxygen
reaction
photocatalysts
for
efficient
production
owing
the
unsatisfactory
productivity.
Herein,
two
new
two-dimensional
piperazine-linked
CoPc-based
covalent
organic
frameworks
(COFs),
namely,
CoPc-BTM-COF
CoPc-DAB-COF,
were
afforded
nucleophilic
substitution
hexadecafluorophthalocyaninato
cobalt(II)
(CoPcF16)
with
1,2,4,5-benzenetetramine
(BTM)
or
3,3′-diaminobenzidine
(DAB).
Powder
X-ray
diffraction
analysis
in
combination
electron
microscopy
a
series
spectroscopic
technologies
reveals
their
crystalline
porous
framework
fully
conjugated
structure
eclipsed
π-stacking
model.
Ultraviolet–visible
diffuse
reflectance
absorption
spectra
unveil
excellent
light
capacity
wide
range
400–1000
nm.
This,
together
enhanced
photo-induced
charge
separation
transport
efficiency
as
disclosed
by
photocurrent
response
photoluminescence
measurements,
endows
as-prepared
COFs
superior
photocatalytic
activity
toward
O2-to-H2O2
conversion
under
visible-light
irradiation
(λ
>
400
nm).
In
particular,
exhibits
record-high
yield
2096
μmol
h–1
g–1
among
COF-based
impressive
apparent
quantum
7.2%
at
630
The
present
result
should
be
helpful
fabricating
high-performance
low-cost
visible-light-driven
photosynthesis.
Nature Communications,
Journal Year:
2023,
Volume and Issue:
14(1)
Published: Nov. 6, 2023
Photocatalytic
two-electron
oxygen
reduction
to
produce
high-value
hydrogen
peroxide
(H2O2)
is
gaining
popularity
as
a
promising
avenue
of
research.
However,
structural
evolution
mechanisms
catalytically
active
sites
in
the
entire
photosynthetic
H2O2
system
remains
unclear
and
seriously
hinders
development
highly-active
stable
photocatalysts.
Herein,
we
report
high-loading
Ni
single-atom
photocatalyst
for
efficient
synthesis
pure
water,
achieving
an
apparent
quantum
yield
10.9%
at
420
nm
solar-to-chemical
conversion
efficiency
0.82%.
Importantly,
using
situ
synchrotron
X-ray
absorption
spectroscopy
Raman
directly
observe
that
initial
Ni-N3
dynamically
transform
into
high-valent
O1-Ni-N2
after
O2
adsorption
further
evolve
form
key
*OOH
intermediate
before
finally
forming
HOO-Ni-N2.
Theoretical
calculations
experiments
reveal
structure
reduces
formation
energy
barrier
suppresses
O=O
bond
dissociation,
leading
improved
production
activity
selectivity.
Journal of the American Chemical Society,
Journal Year:
2023,
Volume and Issue:
145(5), P. 2975 - 2984
Published: Jan. 25, 2023
Multicomponent
reactions
(MCRs)
can
be
used
to
introduce
different
functionalities
into
highly
stable
covalent
organic
frameworks
(COFs).
In
this
work,
the
irreversible
three-component
Doebner
reaction
is
utilized
synthesize
four
chemically
quinoline-4-carboxylic
acid
DMCR-COFs
(DMCR-1-3
and
DMCR-1NH)
equipped
with
an
acid-base
bifunctionality.
These
show
superior
photocatalytic
H2O2
evolution
(one
of
most
important
industrial
oxidants)
compared
imine
COF
analogue
(Imine-1).
This
achieved
sacrificial
oxidants
but
also
in
pure
water
under
oxygen
or
air
atmosphere.
Furthermore,
high
photostability,
durability,
recyclability.
MCR-COFs
thus
provide
a
viable
materials'
platform
for
solar
chemical
energy
conversion.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(19)
Published: March 10, 2023
Four
highly
porous
covalent
organic
frameworks
(COFs)
containing
pyrene
units
were
prepared
and
explored
for
photocatalytic
H2
O2
production.
The
experimental
studies
are
complemented
by
density
functional
theory
calculations,
proving
that
the
unit
is
more
active
production
than
bipyridine
(diarylamino)benzene
reported
previously.
decomposition
experiments
verified
distribution
of
over
a
large
surface
area
COFs
plays
an
important
role
in
catalytic
performance.
Py-Py-COF
though
contains
other
which
induces
high
due
to
dense
concentration
close
proximity
limited
area.
Therefore,
two-phase
reaction
system
(water-benzyl
alcohol)
was
employed
inhibit
decomposition.
This
first
report
on
applying
pyrene-based
generation.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(26)
Published: April 25, 2023
Abstract
Photocatalytic
oxygen
reduction
reaction
(ORR)
offers
a
promising
hydrogen
peroxide
(H
2
O
)
synthetic
strategy,
especially
the
one‐step
two‐electron
(2e
−
ORR
route
holds
great
potential
in
achieving
highly
efficient
and
selectivity.
However,
2e
is
rarely
harvested
underlying
mechanism
for
regulating
pathways
remains
greatly
obscure.
Here,
by
loading
sulfone
units
into
covalent
organic
frameworks
(FS‐COFs),
we
present
an
photocatalyst
H
generation
via
from
pure
water
air.
Under
visible
light
irradiation,
FS‐COFs
exert
superb
yield
of
3904.2
μmol
h
−1
g
,
outperforming
most
reported
metal‐free
catalysts
under
similar
conditions.
Experimental
theoretical
investigation
reveals
that
accelerate
separation
photoinduced
electron‐hole
(e
‐h
+
pairs,
enhance
protonation
COFs,
promote
adsorption
Yeager‐type,
which
jointly
alters
process
two‐step
to
one,
thereby
with
high
Angewandte Chemie International Edition,
Journal Year:
2022,
Volume and Issue:
62(9)
Published: Dec. 30, 2022
The
full
reaction
photosynthesis
of
H2
O2
that
can
combine
water-oxidation
and
oxygen-reduction
without
sacrificial
agents
is
highly
demanded
to
maximize
the
light-utilization
overcome
complex
reaction-process
anthraquinone-oxidation.
Here,
a
kind
oxidation-reduction
molecular
junction
covalent-organic-framework
(TTF-BT-COF)
has
been
synthesized
through
covalent-coupling
tetrathiafulvalene
(photo-oxidation
site)
benzothiazole
(photo-reduction
site),
which
presents
visible-light-adsorption
region,
effective
electron-hole
separation-efficiency
photo-redox
sites
enables
generation
.
Specifically,
record-high
yield
(TTF-BT-COF,
≈276
000
μM
h-1
g-1
)
for
achieved
among
porous
crystalline
photocatalysts.
This
first
work
design
COFs
,
might
extend
scope
in
production.