Proceedings of the National Academy of Sciences,
Journal Year:
2025,
Volume and Issue:
122(16)
Published: April 16, 2025
Mimicking
the
interconvertible
carbon
allotropes
of
2-dimensional
(2D)
graphene
and
1-dimensional
(1D)
nanotubes
(CNTs),
herein
we
report
in
situ
transformation
2D
π-conjugated
covalent
organic
frameworks
(COFs)
sheet
into
1D
nanotubular
structures
via
self-assembly
sheets
at
solvent
interfaces.
The
facile
“roll-sheets”
resulted
coaxial
with
uniform
cross-sectional
diameter,
which
was
realized
for
diazapyrene-based
COFs
but
not
corresponding
pyrene
COF,
although
both
possess
similar
chemical
structures.
Upon
replacing
atoms
2,7-positions
nitrogen,
contrasting
optical
electronic
properties
were
realized,
reflecting
rolled
structure
conjugated
sheets.
exhibited
concerted
electronic-
proton-conducting
nature
stable
conducting
pathways
ambient
conditions.
nitrogen
centers
act
simultaneously
as
site
charge
carrier
doping
proton
acceptors,
evidenced
by
high
photo-
electrical
conductivity,
well
record
conductivity
(σ
=
1.98
S
cm
−1
)
results.
present
COF
serves
a
unique
materials
platform
conduction
wall
core,
respectively.
Advanced Science,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 2, 2025
Efficiently
separating
Li+
over
Mg2+
from
brines
remains
a
significant
challenge
due
to
their
minimal
size
difference
of
only
several
angstroms,
posing
substantial
difficulty
for
traditional
nanofiltration
(NF)
membranes.
Therefore,
nanoconfinement
regulation
strategy
utilizing
porous
covalent
organic
framework
(COF)
layer
is
proposed
precisely
control
the
interfacial
polymerization
(IP)
process,
thereby
obtaining
thin,
uniform
polyamide
(PA)
membrane
high-efficiency
Li+/Mg2+
separation.
The
microenvironment
fundamentally
modulates
both
monomer
spatial
distribution
and
reaction
kinetics
through
confined
space
abundant
interaction
sites
provided
by
COF
layer.
Consequently,
resulting
TpPa-S/PA
exhibits
narrower
pore
distribution,
achieving
an
ion
sieving
precision
0.46
Å.
Due
strict
effect,
separation
factor
exceeded
120,
which
one
two
orders
magnitude
higher
than
all
currently
reported
NF
This
study
addressed
typical
limitations
inherent
in
conventional
membranes,
establishing
promising
foundation
advancing
lithium
extraction
technologies
strategy-regulated
IP
processes.
