Evaluation of shape and size effects on optical properties of ZnO pigment

► The optical properties of ZnO pigments were strongly affected by their size and morphology. ► ZnO particles with diameters greater and smaller than approximately 0.25 and 1.5 μm, respectively, do not scatter light efficiently at any wavelength. ► ZnO particles with diameters in the range of 0.25-1.5 μm, indicated the suitable spectral reflectance. ► The nanoparticle-decorated ZnO pigment revealed the highest spectral reflectance due to their higher surface roughness.