Antifouling energy-efficient coatings based on BiOClxBr1−x microflowers: NIR reflective property and superhydrophobicity

In this work, BiOCl x Br 1−x microflowers were synthesized as building blocks for superhydrophobic NIR reflective coatings. The molar ratio of Cl to Br had a great influence on the microstructure and optical properties of BiOCl x Br 1−x . As the increase of x value, the microflower structure tunes from loose to dense. The NIR solar reflectance of BiOCl x Br 1−x ranges from 0.860 to 0.935. The BiOCl x Br 1−x coatings reduced the inner temperature of the heat box by approximately 3.9 °C. Due to the three-dimensional hierarchical structure of BiOCl x Br 1−x microflowers, superhydrophobic cool coatings can be fabricated on various building materials, such as concretes, aluminum plates, and glasses. Moreover, the superhydrophobic coatings exhibit superior antifouling performance, contributing to retain high NIR reflectance of the coatings for a long time. Therefore, the prepared superhydrophobic NIR reflective coatings with superior antifouling property have great potential to be used for building energy-saving.