Abstract
In the present investigation, La0.65Sr0.3MnO3 (LSM-1) and La0.8Sr0.2MnO3 (LSM-2) nanoceramic powders were prepared by the citrate -nitrate route of auto-combustion with citrate to nitrate (c/n) ratio : 0.50 to assess the effect of these cathode powders on the performance of single SOFC cells. The prepared powders were calcined at 900 degrees C for 4hrs to remove carboneous residues and characterized them using SEM / EDS, XRD, TGA techniques. The electrochemical characterization of LSM cathode powders were carried out by coating these powders (as cathode functional layer CFL-Bottom and current collector layer CL Top) using screen printing on the SOFC half cells (NiO-YSZ+YSZ) procured from CGCRI, Kolkata, India with a cell size of 36 mm dia x1.6 mm. These cells were tested with H-2-O-2 at 700-800 degrees C with the flow rates of 1.2-1.8 L min(-1) of hydrogen and 0.4-0.6 L min(-1) of oxygen. The current density and powder density values obtained for SOFC single cells were 0.85 A cm(-2) (at 0.7 V) and 0.58 W cm(-2) at 800 degrees C with 1.8 L min(-1) hydrogen and 0.60 L min(-1) oxygen. The area surface resistance (ASR) values obtained were similar to 0.52-0.58 Omega cm(2) at 0.7 V at 800 degrees C.