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Current sub-ambient daytime radiative cooling (SDRC) designs are generally evaluated in a well-insulated apparatus to suppress heat convection and conduction with the surrounding environment. In a companion study, we experimentally demonstrated that serial waterborne coatings, which combined particle scattering, sunlight-excited fluorescence, and mid-infrared broadband radiation, exhibited pronounced SDRC effects on various substrates installed on a well-designed rooftop setup under different climatic conditions. In this study, we experimentally show that the coating with yellow-green fluorescence (termed as the FR coating) can achieve meaningful SDRC under real working conditions. When applied to a concrete scale-model building, the FR coating showed a significant SDRC effect compared with other substrates installed on the rooftop cooling device and an assembled corrugated steel house. The average decrease in sub-ambient temperature under direct sunlight was 10.1 ± 1.4 °C with a maximum value of 12.4 °C under a peak solar intensity of 999 W/m2. Moreover, during the coldest day in winter, the maximum sub-ambient temperature reduction during the midday hours was 5.3 °C. The maximum difference between the lowest temperatures of the coated and uncoated scale-model buildings' room interiors was 1.5–1.6 °C. Therefore, excessive heating energy consumption in the winter might be completely compensated for or exceeded by the cooling energy savings in the summer in areas that require both heating and cooling depending on the season. Additionally, the coating possesses excellent weather and salt spray resistance, self-cleaning capabilities, and excellent visible appearance, which are essential for practical applications. Image 1 • The FR coating exhibits a distinct SDRC effect under real working conditions. • The FR coating over a concrete roof surface shows a more notable SDRC effect. • The SDRC design does not necessarily result in detrimental effects in winter. • The FR coating has excellent durability and outstanding self-cleaning properties. [ABSTRACT FROM AUTHOR]

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the authors and the Editor-in-Chief due to insurmountable scientific disagreements over the authorship and section 3.1 in the linked first part of this article, which is being also retracted: "Generic method for creating waterborne coatings with sub-ambient daytime cooling–part I: Optical properties and rooftop cooling effect measurements", Solar Energy Material and Solar Cells 204 (2019):110205. 10.1016/j.solmat.2019.110205. [ABSTRACT FROM AUTHOR]

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the authors and the Editor-in-Chief due to insurmountable scientific disagreements over the authorship and section 3.1 in the linked first part of this article, which is being also retracted: "Generic method for creating waterborne coatings with sub-ambient daytime cooling–part I: Optical properties and rooftop cooling effect measurements", Solar Energy Material and Solar Cells 204 (2019):110205 [ABSTRACT FROM AUTHOR]

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the authors and the Editor-in-Chief due to insurmountable scientific disagreements over the authorship and section 3.1. The linked second part of this article is also being retracted: "Generic method for creating waterborne coatings with sub-ambient daytime cooling–Part II: Cooling effect under real working conditions and key physical properties", Solar Energy Material and Solar Cells 204 (2019):110220. [ABSTRACT FROM AUTHOR]

Waterborne and solvent-based coatings with prominent passive subambient daytime radiative cooling (RC) coatings were fabricated to conserve cooling energy in the summer. Concurrently, water- and alcohol-based superamphiphobic self-cleaning coatings were manufactured and introduced into the RC coatings as topcoats. The contact angles of water and n -hexadecane of the superamphiphobic topcoat containing coating systems were 163.4° and 151.4°, respectively; additionally, the sliding angles of water and n -hexadecane of these systems were 2° and 9°, respectively. Moreover, the introduction of a transparent superamphiphobic topcoat to the RC coatings did not affect their originally high solar reflectance but improved their emissivity values in the atmospheric transparency window, wavelengths between 2.5 and 24 μm, and the entire infrared spectrum due to the presence of plenty of silicon-oxygen bonds formed via hydrolysis and/or alcoholysis reactions and the subsequent co-polycondensation of tetraethoxysilane and 1H,1H,2H,2H-perfluorodecyltriethoxysilane. The solar reflectance of the coating system was 0.986, which is the highest recorded worldwide. The emissivity of the superamphiphobic RC coatings in the atmospheric transparency window was 0.954. The superamphiphobic RC coatings possessed excellent static and dynamic non-wetting capabilities, significantly improving their water resistance, waterproofing properties, and anti-graffiti performance. Additionally, the superamphiphobic RC coatings exhibited outstanding self-cleaning properties, preventing the coating surfaces from being contaminated by dust, soiling, grime, and water/oil-soluble pollutants, thereby enabling them to maintain an extremely high solar reflectance. Water- and alcohol-based superamphiphobic radiative cooling coatings with solar reflectance up to 0.986 were fabricated. The emissivity in the atmospheric transparency window and thereby the overall emissivity were increased to 0.954 and 0.96, respectively, due to the introduction of transparent superamphiphobic topcoats. The contact angles of water and n -hexadecane were 163.4°and 151.4°, respectively, while the sliding angles of water and n -hexadecane were 2°and 9°, respectively. [Display omitted] •The superamphiphobic coating with subambient daytime radiative cooling was produced. •The solar reflectance of the coating was up to 0.986 •The coating's emissivity in the atmospheric transparency window was 0.954 •The coating's contact angles of water and n-hexadecane were higher than 150°. •The coating's sliding angles of water and n-hexadecane were lower than 10°. [ABSTRACT FROM AUTHOR]

Abstract: The physicochemical properties of two newly developed dirt-resistant cool white coatings were systematically measured in light of the relevant standard testing methods, and the influences of dirt accumulation and washing on the long-term cooling performance of cool coatings were investigated and discussed. Both cool white coatings owe their outstanding physicochemical properties to the optimized formulations, high glass transition temperature and minimum film formation temperature of selected aqueous self-curing acrylic emulsions. The high solid content was also influential. Dirt accumulation leads to a decline in the cooling performance of coatings, which may be almost fully restored by simply washing the coatings with a mild soap solution. [Copyright &y& Elsevier]