Catalysis Letters, Vol.144, No.4, 736-743, 2014
Search for a Self-Regenerating Perovskite Catalyst with Ab Initio Thermodynamics II: Cu-Doped Layered Perovskites with K2NiF4 Structure
These years, an "intelligent'' automotive catalyst has been proposed and used in practical applications, which self-regenerates its precious metal nanoparticles during the redox cycles in automotive engines (Nishihata et al. Nature 418: 164, 2002). In eliminating the use of expensive precious metals, a self-regenerating catalyst using non-precious metals such as Cu and Fe is necessary. We investigated the self-regeneration properties of Cu dissolved in layered perovskites with K2NiF4 structure under redox conditions of exhaust gas. Using ab initio thermodynamics calculations, we show that the self-regeneration of Cu on LaCuO3 may be hampered by the formation of La2CuO4, a well-known stable layered perovskite. Next, using the same calculation method, we examined the self-regeneration of Cu on a variety of layered perovskites, and proposed some layered perovskites as potential materials of the self-regenerating catalyst.
Keywords:Self-regenerating perovskite catalyst;Ab initio thermodynamics calculation;Metal solid-solution and segregated states;Cu-doped layered perovskites