Influence of temperature and dopant concentration on structural, morphological and optical properties of nanometric Ce1−xErxO2−δ (x = 0.05–0.20) as a pigment

• New inorganic pigments Ce1−xErxO2−δ (x = 0.05–0.20) were prepared by SPRT method.
• Single-phase form was evidenced for each pigment by XRPD and Raman spectroscopy.
• The XRPD and TEM analysis showed that the crystallites of nanometric dimensions.
• The synthesized pigments show great thermal stability and various pink shades.
• Pigments may be a potential alternative to the classical toxic pink pigments.

Ceramic pigments based on cerium oxide were synthesized by self-propagating room temperature method and their color properties were assessed from the viewpoint of potential environmentally non-toxic pink pigments. Thermal stabilities of the pigments were examined at 600, 900 and 1200 °C. According to X-ray powder diffraction and Raman spectroscopy results, all obtained pigments were single-phase solid solutions of cerium oxide, independent of the concentration of dopants. The X-ray analysis showed that the crystallites were of nanometric dimensions, as recorded and by transmission electron microscopy analysis. Color characteristics of solid solutions, which depended on concentration erbium ions and calcination temperature, and their position in the chromaticity diagram were studied by ultraviolet–visible spectrophotometry, which confirmed potential application of environmentally friendly pigments of desired color. The color efficiency of pigments was also evaluated by colorimetric analysis.