Effects of pigment volume concentration on radiative cooling properties of acrylic-based paints with calcium carbonate and hollow silicon dioxide microparticles

ABSTRACT

Radiative cooling paints offer a sustainable method for reducing energy demand in buildings. This work investigates the effects of particle volume concentration (PVC) of calcium carbonate (CaCO₃) and hollow silicon dioxide (SiO₂) microparticles in acrylic-based paints on cooling capability. Paint solar reflectance increases as the total PVC increases until a peak PVC is reached. The addition of CaCO₃ improves solar reflectance due to an enhancement in near-infrared reflection but decreases thermal emission. The paint, with a total PVC of 0.45 and a CaCO₃:SiO₂ PVC ratio of 1:1, offers the right balance between solar reflection and thermal emissivity and achieves the best cooling performance. This work demonstrates that the CaCO₃-SiO₂ paint system allows tuning of the radiative cooling performance.

KEYWORDS:

• Radiative cooling
• paint pigment
• microparticles
• acrylic paint
• particle volume concentration
• thermal control

Acknowledgements

The authors are also grateful to School of Energy, Environment and Materials, King Mongkut’s University of Technology Thonburi, Thailand, for allowing use of the outdoor testing setup.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by National Research Council of Thailand: [Grant Number 125355]; National Science and Technology Development Agency: [Grant Number P2150385].