Low temperature catalytic conversion of carbon monoxide by the application of novel perovskite catalysts

Abstract

Automobile exhaust contributes the largest sources of carbon monoxide (CO) into the environment. To control this CO pollution, the catalytic converters have been discovered. The catalytic converters have been invented for regulating the CO discharge. There are many types of catalysts have been investigated for CO emission control purposes. Inorganic perovskite-type oxides are fascinating nanomaterials for wide applications in catalysis, fuel cells, and electrochemical sensing. Perovskites prepared in the nanoscale have recently received more attention due to their catalytic nature when used as electrode modifiers. Perovskite catalysts show great potential for CO oxidation catalyst in a catalytic converter for their low cost, high thermal stability and tailoring flexibility. It is active for CO oxidation at a lower temperature. The catalytic activity of these oxides is higher than that of many transition metals compounds and even some precious metal oxides. They represents attractive physical and chemical characteristics such as electronic conductivity, electrically active structure, the oxide ions mobility through the crystal lattice, variations on the content of the oxygen, thermal and chemical stability, and supermagnetic, photocatalytic, thermoelectric and dielectric properties. The surface sites and lattice oxygen species present in perovskite catalysts play an important role in chemical transformations. The partial replacement of cations A and B by different elements, which changes the atomic distance, causes unit cell disturbances, stabilizes various oxidation states or added cationic or anionic vacancies inside the lattice. The novel things disturb the solid reactivity by varying the reaction mechanism on the catalyst surface. Thus, the better cations replacement may represent more activity. There are lots of papers available to CO oxidation over perovskite catalysts but no review paper available in the literature that is represented to CO oxidation.