Synthesis and electrical properties of Fe-doped Y_(0.08)Sr_(0.92)TiO_3 mixed ionic-electronic conductor

摘要

A single phase perovskite Y_(0.08)Sr_(0.92)Ti_(1-X)Fe_xO_(3-δ) (x=0.20,0.40 and 0.50) was fabricated at 1350 C in air by the sol-gel method and its mixed ionic-electronic conductivity was investigated as a function of Fe content. Fe was selected as a B-site dopant with the primary aim to improve the ionic conductivity of SrTiO_3-based materials. With increasing Fe-doping amount, the electrical and ionic conductivities of Y_(0.08)Sr_(0.92)Ti_(1-X)Fe_xO_(3-δ) increased in 400-900 C and 600-950 C, respectively. The possible charge compensation mechanism of Y_(0.08)Sr_(0.92)Ti_(1-X)Fe_xO_(3-δ) can be described as Y_(0.08)Sr_(0.92)Fe_xTi_(0.92-X~(4+))Ti_(0.08~(3+))O_(3-(δ+x/2)) or　Y_(0.08)Sr_(0.92)Fe_xTi_(0.92-x1)~(4+)Ti_(0.82-x2)~(3+)O_(3-(δ+x1/2))(x=x_1+x_2).