Synthesis and Color Evaluation of Tb4+-Doped Na2ZrO3 for Inorganic Yellow Pigments

Tb4+-doped sodium zirconate samples, Na2Zr1−xTbxO3, were synthesized as novel environmentally friendly inorganic yellow pigments by a conventional solid-state reaction method. Their crystal structures, optical properties, and colors characterized. A single-phase form was obtained for the samples in x range of ≤ 0.18, while impurity phases detected sample with = 0.20. All showed strong absorption blue light region, due to charge transfer transition between O2− Tb4+. As result, color became yellow, which is complementary blue, more vivid increasing Tb4+ content region. Among Na2Zr0.82Tb0.18O3 optimal composition, highest yellowness (b* +67.2) pure hue (h° 90.1). Although b* value lower than commercial such BiVO4 ZrSiO4:Pr, this had purer hue. Since composed non-toxic elements, it could be new pigment.