Radiative properties of spectral selective coatings pigmented with TiO₂ nanoparticles

This study is concerned with nanoparticle-pigmented coatings used to control the radiative properties of surfaces exposed to sunlight. The desired coatings increase the near infrared reflectance while decreasing the reflectance of visible light. Both experimental and numerical approaches were followed in achieving the desired spectral behavior. In this study the pigmented coatings were made using TiO₂ as dispersed particles, clear acryl synthetic as the matrix, and standard black paper as the substrate. The spectral reflectance was measured by spectroscopy in the visible and near-infrared regions. The effects of the size distribution and volume fraction of pigment particles and the coating thickness on the spectral reflectance of pigmented coatings are examined in this study.