Dynamic Wettability Behavior of Emerging Ultrawhite Radiative Cooling Paints

Abstract Outdoor radiative cooling surfaces passively lose heat by reflecting solar irradiation and emitting infrared radiation to cold deep space through the atmospheric sky window (8–13 µm), thereby achieving sub‐ambient temperature. Ultrawhite radiative cooling paints are an emerging technology o...

Full description

Saved in:
Bibliographic Details
Main Authors: Orlando G. Rivera González, Abdulrahman K. Aljwirah, Andrea L. Felicelli, Xiulin Ruan, Justin A. Weibel
Format: Article
Language:English
Published: Wiley-VCH 2025-08-01
Series:Advanced Materials Interfaces
Subjects:
Online Access:https://doi.org/10.1002/admi.202500288
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849224574604935168
author Orlando G. Rivera González
Abdulrahman K. Aljwirah
Andrea L. Felicelli
Xiulin Ruan
Justin A. Weibel
author_facet Orlando G. Rivera González
Abdulrahman K. Aljwirah
Andrea L. Felicelli
Xiulin Ruan
Justin A. Weibel
author_sort Orlando G. Rivera González
collection DOAJ
description Abstract Outdoor radiative cooling surfaces passively lose heat by reflecting solar irradiation and emitting infrared radiation to cold deep space through the atmospheric sky window (8–13 µm), thereby achieving sub‐ambient temperature. Ultrawhite radiative cooling paints are an emerging technology offering scalable solutions for cooling and passive water harvesting wherein surface wettability plays a key role. This work, examines how radiative cooling paint pigment and binder formulations affect surface morphology, roughness, and dynamic wettability. Samples are prepared with three different nanoparticulate pigments, calcium carbonate (CaCO3), barium sulfate (BaSO4), and hexagonal boron nitride (hBN); two binders, including an acrylic and a waterborne silicone‐modified polyurethane dispersion (SILIKOPUR 8081); and pigment solid volume concentrations from 0% to 80% v/v. The CaCO3 and BaSO4 pigments produced paints with rougher textures and higher contact angles due to their pigment particle morphology. While high solar reflectance was achieved across various pigment and binder combinations, wettability exhibited a complex trend with pigment concentration, indicating that maximizing reflectance does not necessarily optimize wetting behavior. This expanded understanding on how pigment type, binder and concentration influence wettability, offering pathways to design coatings with tailored spectral and wetting properties for both self‐cleaning paints and passive water harvesting applications
format Article
id doaj-art-848d30e4dcb34be09f1fbb1349f7908b
institution Kabale University
issn 2196-7350
language English
publishDate 2025-08-01
publisher Wiley-VCH
record_format Article
series Advanced Materials Interfaces
spelling doaj-art-848d30e4dcb34be09f1fbb1349f7908b2025-08-25T08:06:18ZengWiley-VCHAdvanced Materials Interfaces2196-73502025-08-011216n/an/a10.1002/admi.202500288Dynamic Wettability Behavior of Emerging Ultrawhite Radiative Cooling PaintsOrlando G. Rivera González0Abdulrahman K. Aljwirah1Andrea L. Felicelli2Xiulin Ruan3Justin A. Weibel4School of Mechanical Engineering and Birck Nanotechnology Center Purdue University West Lafayette IN 47907 USASchool of Mechanical Engineering and Birck Nanotechnology Center Purdue University West Lafayette IN 47907 USASchool of Mechanical Engineering and Birck Nanotechnology Center Purdue University West Lafayette IN 47907 USASchool of Mechanical Engineering and Birck Nanotechnology Center Purdue University West Lafayette IN 47907 USASchool of Mechanical Engineering and Birck Nanotechnology Center Purdue University West Lafayette IN 47907 USAAbstract Outdoor radiative cooling surfaces passively lose heat by reflecting solar irradiation and emitting infrared radiation to cold deep space through the atmospheric sky window (8–13 µm), thereby achieving sub‐ambient temperature. Ultrawhite radiative cooling paints are an emerging technology offering scalable solutions for cooling and passive water harvesting wherein surface wettability plays a key role. This work, examines how radiative cooling paint pigment and binder formulations affect surface morphology, roughness, and dynamic wettability. Samples are prepared with three different nanoparticulate pigments, calcium carbonate (CaCO3), barium sulfate (BaSO4), and hexagonal boron nitride (hBN); two binders, including an acrylic and a waterborne silicone‐modified polyurethane dispersion (SILIKOPUR 8081); and pigment solid volume concentrations from 0% to 80% v/v. The CaCO3 and BaSO4 pigments produced paints with rougher textures and higher contact angles due to their pigment particle morphology. While high solar reflectance was achieved across various pigment and binder combinations, wettability exhibited a complex trend with pigment concentration, indicating that maximizing reflectance does not necessarily optimize wetting behavior. This expanded understanding on how pigment type, binder and concentration influence wettability, offering pathways to design coatings with tailored spectral and wetting properties for both self‐cleaning paints and passive water harvesting applicationshttps://doi.org/10.1002/admi.202500288condensationdynamic wettabilityradiative cooling paintwater harvesting
spellingShingle Orlando G. Rivera González
Abdulrahman K. Aljwirah
Andrea L. Felicelli
Xiulin Ruan
Justin A. Weibel
Dynamic Wettability Behavior of Emerging Ultrawhite Radiative Cooling Paints
Advanced Materials Interfaces
condensation
dynamic wettability
radiative cooling paint
water harvesting
title Dynamic Wettability Behavior of Emerging Ultrawhite Radiative Cooling Paints
title_full Dynamic Wettability Behavior of Emerging Ultrawhite Radiative Cooling Paints
title_fullStr Dynamic Wettability Behavior of Emerging Ultrawhite Radiative Cooling Paints
title_full_unstemmed Dynamic Wettability Behavior of Emerging Ultrawhite Radiative Cooling Paints
title_short Dynamic Wettability Behavior of Emerging Ultrawhite Radiative Cooling Paints
title_sort dynamic wettability behavior of emerging ultrawhite radiative cooling paints
topic condensation
dynamic wettability
radiative cooling paint
water harvesting
url https://doi.org/10.1002/admi.202500288
work_keys_str_mv AT orlandogriveragonzalez dynamicwettabilitybehaviorofemergingultrawhiteradiativecoolingpaints
AT abdulrahmankaljwirah dynamicwettabilitybehaviorofemergingultrawhiteradiativecoolingpaints
AT andrealfelicelli dynamicwettabilitybehaviorofemergingultrawhiteradiativecoolingpaints
AT xiulinruan dynamicwettabilitybehaviorofemergingultrawhiteradiativecoolingpaints
AT justinaweibel dynamicwettabilitybehaviorofemergingultrawhiteradiativecoolingpaints