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”. 2013 Elsevier Ltd. All rights reserved.