New vanadium doped calcium titanate ceramic pigment

In this paper a new pink vanadium doped calcium titanate Ca(VxTi1−x)O3 ceramic pigment in conventional ceramic glazes is obtained by ceramic route and characterized. The limit of solid solution is near by x = 0.2, higher amounts of vanadium crystallizes Ca2V2O7 which dilute the real amount of saturated Ca(VxTi1−x)O3 solid solution and diminish the intensity of colour. The unit cell parameter measurements of Ca(VxTi1−x)O3 agrees with the substitution of Ti4+ by V5+ that is associated to a V5+–O charge transfer at 420 nm on UV–vis–NIR spectra of 5% glazed samples that explain the pink colour obtained. In order to avoid the limitation due to the suppressing of oxygen vacancies by high valence cation V5+ substitution in a Ti4+ site of CaTiO3 perovskite for to preserve the charge neutrality of the lattice; Fe3+ and V5+ codoped samples Ca(FexVxTi1−2x)O3x = 0.1, 0.2 and 0.3 were prepared and show a brown colour fired 1000 °C, but 5% glazed do not produce colour indicating that iron codoping inhibits the pigmenting capacity of vanadium doped CaTiO3 perovskite.