Microstructure and ionic conductivity of Sr- and Mg-doped LaGaO3

摘要

Samples of Sr- and Mg-doped LaGaO3 (LSGM) with various concentrations of Sr and Mg were prepared by using solid-state reaction method. Results show that ionic conductivities increase with the increase of relative densities. It can also be known that the optimized concentration in ${rm La}_{1-x} {rm Sr}_{x} {rm Ga}_{1-y} {rm Mg}_{y} {rm O}_{3-0.5(x+y)}$ with high conductivity is LSGM1520 or LSGM2015. The results also show that, in various concentrations of LSGM, equiaxed, rode-like, polygonal secondary phases such as LaSrGaO4 or LaSrGa3O7 were detected besides (La,Sr)(Ga,Mg)O3 by means of SEM and EDX. With the increase of doped elements, i.e. x + y, the grain size increases.