Synthesis and Characterization of Yellow Pigments Fabricated by Sol-Gel and Solid-State Reaction Routes

Abstract

Novel environment-friendly near-infrared reflective Y5.2Nd0.8MoO12+σ pigments were fabricated by sol-gel and solid-state reaction routes, and the properties of both pigments were compared. The pigments were characterized by XRD, SEM, CIE-L*a*b* color-measurements, and UV-vis-NIR spectroscopy. The results show that pigments obtained by sol-gel routes crystallize completely at 900 °C, much lower than 1300 °C of solid-state reaction routes. Nano-size pigments fabricated by sol-gel routes possess an average grain size of ~ 50 nm, largely finer than 3 μm of solid-state reaction ones. Moreover, the sol-gel processed pigments show a higher near-infrared reflectance than solid-state reaction ones, which are 98.3 % and 91.7 %, respectively, but with a slightly light yellow color hue.