The effect of partial substitution of Bi on colour properties and thermal stability of Bi.sub.xPr.sub.1-xFeO.sub.3 pigments

• Published in: Journal of thermal analysis and calorimetry Vol. 138; no. 6; pp. 4303 - 4312
• Main Authors: Luxová, Jana, Sulcová, Petra
• Format: Journal Article
• Language: English
• Published: Springer 01.12.2019
• Subjects: Diffraction; X-rays
• ISSN: 1388-6150; 1588-2926
• DOI: 10.1007/s10973-019-08686-8

The samples of Bi.sub.xPr.sub.1-xFeO.sub.3 (x = 0-0.3) were prepared by conventional ceramic method. The main aim of this work was to focus on determination of influence of partial Bi substitution for Pr on chromaticity and thermal stability. The formation temperature of the orthoferrites was chosen according to the results of DTA/TG analysis. X-ray powder diffraction analysis showed that solid solutions with orthorhombic structure were created. Results of the work proved that Bi substitution for Pr in PrFeO.sub.3 has significant impact on colour properties and thermal stability. Start of sintering of PrFeO.sub.3 was detected at 1086 °C and due to substitution of Bi.sup.3+ decreased to 956 °C (for x = 0.3). Thermal stability of the samples with x = 0.2 and x = 0.3 was limited at 1371 °C and 1360 °C, respectively. However, final colour was positively affected by the addition of Bi.sup.3+. Colour shades of powder shifted from yellowish brown to reddish brown with increasing amount of Bi ions. Very interesting colours of different deep yellowish and reddish brown shades were obtained after their application into organic binder. Mean particle size for all milled compounds prepared at 1000 °C was around 1 [mu]m and for samples calcined at 1100 °C ranged between 1 and 1.6 [mu]m.