The influence of short thermal treatment on structure, morphology and optical properties of Er and Pr doped ceria pigments: Comparative study

Abstract

Potential non-toxic pink and red ceramic pigments based on CeO2 were successfully synthesized by self-propagating room temperature method and thermally treated at 600, 900 and 1200 degrees C for 15 min. The structure, morphology and optical properties, as well as thermal stability of Ce1-xErxO2-delta and Ce1-xPrxO2-delta (x = 0.05) were examined. Single-phase composition of all obtained CeO2 pigments was confirmed using XRPD method and Raman spectroscopy and it was not dependent on temperature. The mechanism of structural behaviour was thoroughly examined using Raman and FTIR spectroscopy. Nanometric dimensions of the crystallites of all pigments were confirmed using XRPD, TEM and FE-SEM analysis. Colour properties were dependent on the temperature treatment, and their position in the chromaticity diagram was studied using UV/VIS spectrophotometry. Colour efficiency measurements were supplemented by colorimetric analysis. It is proved that all samples are thermally stable in the investigated temperature range (up to 1200 degrees C), and their potential application as environmentally friendly pigments of desired colour is confirmed.