ACS Omega,
Год журнала:
2024,
Номер
9(50), С. 49494 - 49502
Опубликована: Дек. 4, 2024
The
cooling
power
of
radiative
(RC)
coatings
depends
not
only
on
the
properties
coating
but
also
environmental
variables.
In
tropical
environments,
performance
RC
deteriorates
due
to
high
humidity
and
solar
radiation.
Previous
studies
focused
developing
solar-reflective
achieve
subambient
in
environments.
However,
these
have
demonstrated
ability
be
used
at
a
large
scale,
mainly
their
cost
or
less
durability.
Herein,
we
test
an
paint
composed
TiO2
polydimethylsiloxane
(PDMS)
three
different
cities
with
moderate
levels.
Though
significant
reduction
internal
temperature
paint-coated
aluminum
(Al)
box
is
observed,
compared
uncoated
Al
box,
both
achieved.
A
comprehensive
analysis
conducted
clarify
reasons
behind
inability
attain
cooling.
Atmosphere,
Год журнала:
2025,
Номер
16(1), С. 95 - 95
Опубликована: Янв. 16, 2025
Passive
daytime
radiative
cooling
(PDRC)
has
emerged
as
a
promising,
electricity-free
approach
that
reflects
sunlight
while
radiating
heat
through
the
atmospheric
transparent
window.
However,
design
and
optimization
of
PDRC
materials
remain
challenging,
requiring
significant
time
resources
for
experimental
numerical
modeling
efforts.
In
this
work,
we
developed
machine
learning
(ML)-driven
to
predict
scattering
efficiency
in
wavelength
0.3–2.5
μm,
with
aim
eventually
optimizing
microstructural
materials.
By
employing
ML
models
such
linear
regression,
neural
networks,
random
forests,
aimed
optimize
across
different
pore
sizes
mixed-pore-size
configurations.
As
result,
forest
model
demonstrated
superior
prediction
performance
minimal
error,
effectively
capturing
complex,
non-linear
interactions
between
material
features.
We
also
leveraged
data
transformation
techniques
one-hot
encoding
generative
predictions
The
presented
ML-driven
platform
serves
valuable
open
resource
researchers,
facilitating
rapid
cost-effective
accelerating
development
sustainable
technologies.
Applied Physics Letters,
Год журнала:
2025,
Номер
126(11)
Опубликована: Март 1, 2025
Passive
solar
heating
and
radiative
cooling
attracted
lots
of
attention
in
global
energy
consumption
reduction
due
to
their
unique
electricity-free
advantage.
However,
static
single
radiation
or
would
lead
over-cooling
over-heating
cold
hot
weather,
respectively.
How
achieve
effective
self-adaptive
thermoregulation
is
critical
for
dynamic
thermal
management.
Hence,
this
work,
a
strategy
was
designed
by
coupling
latent
heat
storage
release
with
reversible
cooling.
A
commercial
memory
alloy
could
realize
at
the
temperature
between
high
reflectance
R¯solar
=
0.95
emittance
ε¯LWIR
0.93,
absorptance
α¯solar
0.92
low
ε¯IR
0.08.
High
conductive
phase
change
material
further
improve
performance
∼136
J
g−1,
conductivity
3.4
W
m−1
K−1,
resulting
superior
than
(39.9
vs
36.9
°C)
(33.8
35.5
°C).
The
maximum
increase
be
12.7
°C
situation,
drop
8.3
situation.
Energy
calculation
showed
that
sample
save
68%–90%
annual
compared
common
roof,
indicating
spectral
regulation
can
greatly
total
Cooling
environments
are
a
pervasive
need
in
our
society,
with
conventional
air
conditioners
being
the
most
popular
approach.
However,
rely
heavily
on
electricity
and
Freon,
chemical
that
depletes
ozone
contributes
to
greenhouse
gas
effects.
To
address
this
issue,
passive
daytime
radiative
coolers
(PDRCs)
have
been
proposed
achieve
cooling
by
simultaneously
reflecting
sunlight
allowing
internal
heat
escape
without
electricity.
Despite
their
potential,
high-performance
PDRCs
composed
of
thick
polymer
films,
which
increases
material
costs
during
PDRC
preparation
limits
thermal
transport.
In
work,
we
introduced
an
economical
scalable
solvent
evaporation-based
method
prepare
relatively
thin
hierarchically
micro-
nanostructured
poly(vinylidene
fluoride-trifluoroethylene)
via
crystallinity
alteration.
Particularly,
find
key
generating
nanosized
pores
is
remove
water
residual
within
film
sample
annealing,
significantly
enhances
scattering
efficiency
across
solar
spectrum.
With
design,
demonstrate
effective
outdoor
environment,
achieving
temperature
Δ2.5
°C,
thickness
only
215
μm.
Furthermore,
model
suggested
applying
could
lead
annual
energy
savings
up
∼39%
warmer
climates
country
715
GJ
nationwide.
Developing
reduced
thickness,
such
as
one
discussed
here,
imperative
for
implementing
sustainable
solutions
reducing
carbon
footprint.
Journal of Materials Chemistry A,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 1, 2025
A
nanostructured
perfluoropolymer
paint
with
high
solar
reflectance
and
selective
infrared
emittance
has
been
developed,
highlighting
the
importance
of
optimizing
chemical
structure
polymer
binder
for
radiative
cooling.
Polymer Composites,
Год журнала:
2025,
Номер
unknown
Опубликована: Апрель 12, 2025
Abstract
Passive
cooling
materials
represent
an
effective
and
environmentally
friendly
strategy
for
achieving
energy
efficiency.
The
passive
performance
can
be
achieved
by
shielding
partial
solar
irradiance
transmitting
infrared
radiation
emitted
the
human
body
or
surroundings.
One
solution
is
to
utilize
Mie
scattering
theory
of
nanoparticles
(NPs)
dispersed
in
polymers
adjust
spectral
transmissivity.
However,
often
limited
agglomeration
NPs
polymer
matrix.
In
this
study,
spherical
titanium
dioxide
(TiO
2
)
with
a
diameter
350
nm
were
surface‐modified
different
concentrations
durations
silane
coupling
agent
3‐
(trimethoxy
silyl)
propyl
methacrylate
(KH‐570).
Then,
wt%
TiO
extruded
low‐density
polyethylene
(LDPE)
obtain
well‐dispersed
composites.
optimal
was
using
treated
20
KH‐570
8
h.
fabricated
composites
exhibited
average
irradiation
rate
58.0%,
atmospheric
window
transmissivity
97.1%,
10.0°C
under
direct
exposure.
This
study
presented
economical
approach
potential
applications
building
envelopes,
industrial
facilities,
personal
thermal
management
systems.
Highlights
modified
varying
durations.
Polymer
hybridized
LDPE
fabricated.
excellent
performance.
transmittance
across
windows.
Nano Letters,
Год журнала:
2024,
Номер
24(50), С. 16143 - 16150
Опубликована: Дек. 6, 2024
Solar
evaporation
designs
show
great
promise
in
water
harvesting
without
electricity
inputs.
Unfortunately,
they
have
been
heavily
limited
by
a
low
yield.
To
overcome
this
challenge,
we
introduced
new
architecture
featuring
both
system-level
and
materials-level
designs.
At
the
system
level,
implemented
macropatterned
with
decoupled
design
for
condensation
to
enhance
yield
efficiency.
This
also
ensures
that
condensed
droplets
do
not
block
solar
process.
materials
selective
heating
radiative
cooling
were
applied
improve
passive
performance.
As
proof
of
concept,
our
showed
an
indoor
collection
rate
2.06
kg
m-2
h-1
under
one
sun
average
outdoor
1.85
over
five
consecutive
days.
The
decoupled,
all-passive,
offers
substantial
potential
commercial
applications
toward
mitigating
global
scarcity.
Passive
cooling
technologies
have
shown
great
interest
recently
due
to
their
free
electricity,
especially
for
radiative
(RC),
and
evaporation
(EC).
While
single-mode
passive
is
often
limited
by
environmental
conditions,
such
as
sunlight,
clouds,
humidity,
resulting
in
a
performance.
To
address
these
issues,
an
adhesive
hydrogel
paint
designed
heat
dissipation
the
daytime
or
high
workload
via
coupled
(REC),
which
also
can
realize
water
self-replenishment
at
night
low
RC-assisted
adsorption
moisture
capture.
Solar
reflectance
R¯solar${{\bar{R}}_{{\mathrm{solar}}}}$
=
0.91
thermal
emittance
ε¯LWIR${{\bar{\varepsilon
}}_{{\mathrm{LWIR}}}}$
0.94
are
obtained
RC.
Excellent
performance
be
achieved
painting
it
on
3D
W-shaped
substrate.
Compared
with
flat
RC
paint,
REC
W-shape
substrate
achieves
temperature
drop
of
5.4
°C
heating
density
100
W
m-2,
further
increased
11.4
400
m-2
multi-passive
strategies.
This
structural
material
design
provides
potential
outdoor
dissipation.
