La2−xCexCu1−yZnyO4 perovskites for high temperature water-gas shift reaction

The performance of La2−xCexCu1−yZnyO4 perovskites as catalysts for the high temperature water-gas shift reaction (HT-WGSR) was investigated. The catalysts were characterized by EDS, XRD, BET surface area, TPR, and XANES. The results showed that all the perovskites exhibited the La2CuO4 orthorhombic structure, so the Pechini method is suitable for the preparation of pure perovskite. However, the La1.90Ce0.10CuO4 perovskite alone, when calcined at 350/700 °C, also showed a (La0.935Ce0.065)2CuO4 perovskite with tetragonal structure, which produced a surface area higher than the other perovskites. The perovskites that exhibited the best catalytic performance were those calcined at 350/700 °C and, among these, La1.90Ce0.10CuO4 was outstanding, probably because of the high surface area associated with the presence of the (La0.935Ce0.065)2CuO4 perovskite with tetragonal structure and orthorhombic La2CuO4 phase.