Microstructure and electrochemical behavior of La _0.8Sr _0.2MnO ₃ deposited by solution precursor plasma spraying

Solution precursor plasma spraying (SPPS) was employed to prepare porous La _0.8Sr _0.2MnO ₃ (LSM) cathode for solid oxide fuel cell (SOFC). The surface morphology and microstructure of the LSM deposits were characterized by SEM. The phase structure of LSM was analyzed by XRD. The electrochemical behavior was investigated through the impedance spectroscopy. The effect of spray distance and annealing treatment on SPPS LSM microstructure was examined. Annealing at 1050°C for 2 h in air, the coherent porous films of the perovskite phase with a fine microstructure were presented. The results show that the microstructure of SPPS LSM cathode exhibits a significant influence on the cathode polarization. The lowest specific surface resistance of 0.3 Ω · cm ² is obtained at 1000°C for SPPS LSM cathode deposited at a spray distance of 60 mm. SPPS is a promising process to fabricate SOFC cathode with tailoring of the desired phase and microstructure.