Electrical conductivity and chemical stability of BaCe0·8 − x A x Gd0·2O3 − δ (A = In, Zr, Ta; x = 0, 0·1) ceramics
Bulletin of Materials Science
BaCe 0·8−x A x Gd 0·2 O 3−δ (A = In, Zr, Ta; x = 0, 0·1) ceramics were synthesized by solid-state reaction method. Microstructure and electrical properties of BaCe 0·8−x A x Gd 0·2 O 3−δ ceramics were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and complex impedance analysis at intermediate temperatures of 573-1073 K in different atmospheres. BaCe 0·8 Gd 0·2 O 3−δ , BaCe 0·7 In 0·1 Gd 0·2 O 3−δ and BaCe 0·7 Zr 0·1 Gd 0·2 O 3−δ ceramics exhibit a single
... exhibit a single cubic perovskite structure. BaCe 0·7 In 0·1 Gd 0·2 O 3−δ ceramic has the highest conductivity of 4·6 × 10 −2 S·cm −1 in air at 1073 K. BaCe 0·7 In 0·1 Gd 0·2 O 3−δ and BaCe 0·7 Zr 0·1 Gd 0·2 O 3−δ ceramics exhibit an excellent chemical stability against boiling water. Indium is a suitable doping element to promote the sintering densification and to enhance both electrical conductivity and chemical stability of Gd-doped BaCeO 3 at operating temperatures.