Synthesis and characterization of novel yellow-green Al-doped Y3Fe5O12 nano-pigments with high NIR reflectance

The pigments with high near-infrared (NIR) reflectance hold great promise toward both fundamental types of researches and applications for the realization of comfortable indoor-temperature by mitigating urban heat island effect. However, the facile yet simple method for the NIR reflective pigments with bright color and non-toxic feature remains a huge challenge, limiting their practical application. Herein, we proposed a mild and universal method of solution combustion for constructing the non-toxic and NIR reflective yellow-green pigments of Al-doped Y 3 Fe 5 O 12 . The Y 3 Fe 4 AlO 12 pigment presented a high NIR reflectance of 87.66%, and an outstanding acid/alkali resistance. Moreover, the pigment had an impressive color performance (L* = 78.72, a* = − 4.05, b* = 40.04). Besides, the practical near-infrared reflection performance revealed that the transient surface temperature of the Y 3 Fe 4 AlO 12 pigment was 7.6 °C lower than that of the pigment with similar color on the market. This research supplied high NIR reflecting pigments of Y 3 Fe 5−x Al x O 12 as promising coatings for roofs and exterior walls of buildings, acting as a favorable solution for urban heat island effect.