Crystal structure and optical properties of YMnO3 compound with high near-infrared reflectance

The new application of YMnO3 as a high near-infrared (NIR) reflective inorganic pigment has been developed. Single-phased perovskite nanocrystalline YMnO3 samples with different average sizes have been synthesized through a polyacrylamide gel route. With the calcination temperature increasing from 700 °C to 900 °C, the color of the samples is blue-green, and the broad band value decreases from 1.89 to 1.58 eV due to the O2p–Mn3d charge-transfer transition. The NIR reflectance and solar reflectance values of corresponding pigmented coating increase from 51.4% to 53.4% and from 23.9% to 32.5%, respectively, which are higher than that of commercially available roofing products of the same color. The prepared YMnO3 pigment can be well served as colored “cool colorant”.

► Nanocrystalline YMnO3 samples have been synthesized through a polyacrylamide gel route.
► The samples are blue-green, and the band gap decreases from 1.89 to 1.58 eV.
► The NIR reflectance of corresponding pigmented coatings increases from 51.4% to 53.4%.
► The solar reflectance of corresponding pigmented coatings increases from 23.9% to 32.5%.
► The prepared YMnO3 pigments can be well served as colored “cool colorant”.