Thermal expansion and lattice parameter of solid electrolyte based on cerate-zirconate ceramics

As a potential electrolyte for proton conducting solid oxide fuel cells, cerate-zirconate ceramics that belong to perovskite type-oxides are widely explored world-wide. This paper presents the thermal expansion of the electrolyte that becomes one of the crucial properties in the fuel cell fabrication. A sol gel method was used to prepare BaCe_0.54Zr_0.36Y_0.1O_3-δ (BCZY) proton conductor with a combination of the high proton conductivity of barium cerate and good chemical stability of barium zirconate. After calcined at 1100°C for 10 h, the single-phase powder was pressed to become a pellet with 13 mm in diameter and 2 mm thickness. Scanning electron microscope (SEM) was done to observe the morphology of sample and lattice parameter was determined at room temperature using XRD. The thermal expansion of BCZY electrolyte has been investigated in air by using dilatometer in the temperature range of 30°C - 1000°C at a heating rate of 10°C/min. The influence of thermal on the form of linear expansion of pellet BCZY as a function of temperature, ΔL/L˳ = f(T) which is ΔL is the length change and L_o is the initial length has been plotted. The thermal expansion coefficient of BCZY is 8.53×10⁻⁶/K with lattice parameter calculated is 4.344Å.