The uniform particle size of the samples can be noticed from
the SEM photographs (Fig. 2) of Ce0.95MxPr0.05xO2 (M = Mn
and Si, x ranges from 0 to 0.05) pigments. The particle size of
Mn substituted pigments is found to be in the range 2–5 mm and
that of Si substituted pigments in the range of 0.5–1 mm. Si4+
co-doped Pr4+–CeO2 exhibits smaller particles compared to the
Mn4+ co-doped ceria pigments and this is clear from the
increased lightness of the Ce0.95SixPr0.05xO2 (Table 1). The
effective solid solution formation was checked by energy
dispersive spectrophotometer (EDS) analysis attached with
TEM. Fig. 3(a) and (b) shows the micrographs and EDS