Synthesis, structure and total conductivity of A-site doped LaTiO3−δ perovskites

• A-site divalent alkaline earth metal doped LaTiO3−δ perovskites were synthesised by sol–gel method.
• Structural studies revealed no change in crystal symmetry but change in cell dimensions after doping.
• After doping divalent cations in A-site, an enhancement in total conductivity was observed in LaTiO3−δ.
• Temperature dependent electrical property was observed in all synthesised perovskites.

Oxygen deficient perovskites LaTiO3−δ and La0.8A0.2TiO3−δ (A = Ba, Sr, Ca) were synthesized by sol–gel method. The effect of divalent dopants on microstructure is investigated in detail using X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The oxidation states of La3+ and Ti3+ ions have been deduced using X-ray Photoelectron Spectroscopy (XPS). Impedance spectroscopy was used to analyze the total conductivity, an increase in conductivity was observed after doping in the A-site with divalent cations Ba, Ca and Sr. Among the investigated perovskites La0.8Ca0.2TiO3−δ exhibited the maximum conductivity of 1.22 × 10−2 S/cm in air atmosphere at 650 °C.