Muhammad Fuad Abdul Hakim

Universitas Merdeka Madiun

Fajar Subekti

Universitas Merdeka Madiun

DOI: https://doi.org/10.19184/rotor.v19i1.60006 

ABSTRACT 

The need for cooling is inseparable from human activities. Active cooling, which relies on external energy, remains the dominant approach to meeting this need. As cooling demand increases, energy consumption will correspondingly rise. Passive cooling has emerged as an alternative that can provide cooling without requiring external energy. One of the developments in passive cooling is radiative cooling paint (RCP), a type of paint that emits thermal radiation into the atmosphere while reflecting incoming solar irradiation, thereby reducing the temperature of surfaces it coats. The pigment, as a constituent of RCP, plays a significant role in determining its temperature reduction performance. However, previous studies tested different pigment types under varying locations, environmental conditions, and substrates, making accurate comparisons difficult. Therefore, this study aimed to compare the temperature reduction performance of RCP composed of five types of pigments, namely calcium carbonate (CaCO3), barium sulfate (BaSO4), magnesium oxide (MgO), titanium dioxide (TiO2), and silicon dioxide (SiO2), tested at the same location, under the same environmental conditions and time, and using the same substrate. All five RCP samples were applied onto aluminum plates and tested under direct sunlight from 09.30 to 14.30. The results showed that the RCP sample containing BaSO4 pigment exhibited the greatest average temperature reduction (7.1 ºC), followed by CaCO3 (6.8 ºC), TiO2 (5.2 ºC), SiO2 (4.6 ºC), and MgO (3.5 ºC). These differences in performance are attributed to variations in band gap, refractive index, and pigment color among the five pigment types.

Keywords: energy, pigment, radiative cooling paint, temperature reduction

REFERENCES

[1] Dwivedi, P., Sudhakar, K., Soni, A., Solomin, E. and Kirpichnikova, I., 2020. Advanced cooling techniques of PV modules: A state of art. Case Stud. Therm. Eng., Vol. 21, pp. 1–17. doi: 10.1016/j.csite.2020.100674.

[2] Mandal, J., Yang, Y., Yu, N. and Raman, A.P., 2020. Paints as a scalable and effective radiative cooling technology for buildings. Joule, Vol. 4 (7), pp. 1350–1356. doi: 10.1016/j.joule.2020.04.010.

[3] Chen, M., Pang, D., Chen, X., Yan, H. and Yang, Y., 2022. Passive daytime radiative cooling: Fundamentals, material designs, and applications. EcoMat, Vol. 4 (1). doi: 10.1002/eom2.12153.

[4] Altamimi, M.M.S., Saeed, U. and Al-Turaif, H., 2023. BaSO4/TiO2 microparticle embedded in polyvinylidene fluoride-co-hexafluoropropylene/polytetrafluoroethylene polymer film for daytime radiative cooling. Polymers, Vol. 15 (19), p. 3876. doi: 10.3390/polym15193876.

[5] Lim, H., Chae, D., Son, S., Ha, J. and Lee, H., 2022. CaCO3 micro particle-based radiative cooling device without metal reflector for entire day. Mater. Today Commun., Vol. 32, p. 103990. doi: 10.1016/j.mtcomm.2022.103990.

[6] Li, X., Peoples, J., Huang, Z., Zhao, Z., Qiu, J. and Ruan, X., 2020. Full daytime sub-ambient radiative cooling in commercial-like paints with high figure of merit. Cell Rep. Phys. Sci., Vol. 1 (10), p. 100221. doi: 10.1016/j.xcrp.2020.100221.

[7] Atiganyanun, S. and Kumnorkaew, P., 2023. Effects of pigment volume concentration on radiative cooling properties of acrylic-based paints with calcium carbonate and hollow silicon dioxide microparticles. Int. J. Sustain. Energy, Vol. 42 (1), pp. 612–626. doi: 10.1080/14786451.2023.2221082.

[8] Joseph, W.R., Tan, J.Y., Koyande, A.K., Khoiroh, I., Joynson, J. and Willis, S., 2023. Subambient passive radiative cooling effects of barium sulfate and calcium carbonate paints under Malaysia's tropical climate. Environ. Sci. Adv., Vol. 2 (12), pp. 1662–1679. doi: 10.1039/D3VA00161J.

[9] Li, X., Peoples, J., Yao, P. and Ruan, X., 2021. Ultrawhite BaSO4 paints and films for remarkable daytime subambient radiative cooling. ACS Appl. Mater. Interfaces, Vol. 13 (18), pp. 21733–21739. doi: 10.1021/acsami.1c02368.

[10] Felicelli, A. et al., 2024. Efficient radiative cooling of low-cost BaSO4 paint-paper dual-layer thin films. Nanophotonics, Vol. 13 (5), pp. 639–648. doi: 10.1515/nanoph-2023-0642.

[11] Okoro, H.O. et al., 2024. Preliminary experimental performance assessment of ultra-white barium sulphate for sub-ambient radiative cooling in Abuja, Nigeria. Int. J. Adv. Sci. Eng., Vol. 10 (3), pp. 3508–3516. doi: 10.29294/IJASE.10.3.2024.3508-3516.

[12] Das, P., Rudra, S., Maurya, K.C. and Saha, B., 2023. Ultra-emissive MgO-PVDF polymer nanocomposite paint for passive daytime radiative cooling. Adv. Mater. Technol., Vol. 8 (24). doi: 10.1002/admt.202301174.

[13] Mishra, B.R., Sundaram, S. and Sasihithlu, K., 2024. Design of radiative cooling paint coating and insights into its sub-ambient cooling behaviour. arXiv Preprints. doi: 10.48550/arXiv.2401.11765.

[14] Song, J. et al., 2022. Durable radiative cooling against environmental aging. Nat. Commun., Vol. 13 (1), p. 4805. doi: 10.1038/s41467-022-32409-7.

[15] Suichi, T., Ishikawa, A., Hayashi, Y. and Tsuruta, K., 2018. Performance limit of daytime radiative cooling in warm humid environment. AIP Adv., Vol. 8 (5). doi: 10.1063/1.5030156.

[16] Putra, M.A., Hakim, M.F.A. and Permana, D.I., 2026. Role of pigment volume concentration in controlling optical properties and cooling performance of radiative coatings. Int. J. Heat Technol., Vol. 44 (1). doi: 10.18280/ijht.440123.

[17] Bergman, T.L., Lavine, A.S., Incropera, F.P. and Dewitt, D.P., 2011. Fundamentals of Heat and Mass Transfer. 7th ed. John Wiley & Sons, Inc.

[18] Sutherland, B.R., 2020. Solar materials find their band gap. Joule, Vol. 4 (5), pp. 984–985. doi: 10.1016/j.joule.2020.05.001.

[19] Tran, T.C., Anh, N.D.Q. and Loan, N.T.P., 2020. Comparison of calcium carbonate and titania particles on improving color homogeneity and luminous flux of WLEDs. TELKOMNIKA (Telecommunication Computing Electronics and Control), Vol. 18 (5), p. 2690. doi: 10.12928/telkomnika.v18i5.13552.

[20] Ropp, R.C., 2013. Group 16 (O, S, Se, Te) alkaline earth compounds. In: Encyclopedia of the Alkaline Earth Compounds. Elsevier, pp. 105–197. doi: 10.1016/B978-0-444-59550-8.00003-X.

[21] Tang, H. et al., 2022. Radiative cooling performance and life-cycle assessment of a scalable MgO paint for building applications. J. Clean. Prod., Vol. 380, p. 135035. doi: 10.1016/j.jclepro.2022.135035.

[22] Stephens, R.E. and Malitson, I.H., 1952. Index of refraction of magnesium oxide. J. Res. Natl. Bur. Stand., Vol. 49 (4), p. 249. doi: 10.6028/jres.049.025.

[23] Schifferle, L., Speziale, S. and Lobanov, S.S., 2022. High-pressure evolution of the refractive index of MgO up to 140 GPa. J. Appl. Phys., Vol. 132 (12). doi: 10.1063/5.0106626.

[24] Tasisa, Y.E., Sarma, T.K., Krishnaraj, R. and Sarma, S., 2024. Band gap engineering of titanium dioxide (TiO2) nanoparticles prepared via green route and its visible light driven for environmental remediation. Results Chem., Vol. 11, p. 101850. doi: 10.1016/j.rechem.2024.101850.

[25] Rocquefelte, X. et al., 2005. Analysis of the refractive indices of TiO2, TiOF2, and TiF4: Concept of optical channel as a guide to understand and design optical materials. Inorg. Chem., Vol. 44 (10), pp. 3589–3593. doi: 10.1021/ic048259w.

[26] Khachaturova, T.A., But'ko, V.G. and Gusev, A.A., 2022. Electronic structure and properties of two-dimensional silicon dioxide. JETP Lett., Vol. 115 (1), pp. 41–44. doi: 10.1134/S0021364022010106.

[27] Engelhorn, K. et al., 2015. Electronic structure of warm dense silicon dioxide. Phys. Rev. B, Vol. 91 (21), p. 214305. doi: 10.1103/PhysRevB.91.214305.

[28] Naskar, S., Wolter, S.D., Bower, C.A., Stoner, B.R. and Glass, J.T., 2008. Effect of film chemistry on refractive index of plasma-enhanced chemical vapor deposited silicon oxynitride films: A correlative study. J. Mater. Res., Vol. 23 (5), pp. 1433–1442. doi: 10.1557/JMR.2008.0176.

[29] Dhankhar, M., Singh, O.P. and Singh, V.N., 2014. Physical principles of losses in thin film solar cells and efficiency enhancement methods. Renew. Sustain. Energy Rev., Vol. 40, pp. 214–223. doi: 10.1016/j.rser.2014.07.163.

[30] Diebold, M.P., 2014. Application of Light Scattering to Coatings: A User's Guide. Delaware: Springer.

[31] Paminto, J. and Yulianti, I., 2021. The effect of surface color on the absorption of solar radiation. Phys. Comm., Vol. 5 (1), pp. 27–32.