| abstract |
The invention relates to a gasoline vehicle three-way catalyst and a preparation method thereof, belonging to the technical field of preparation of gasoline vehicle catalysts. The catalyst uses cordierite honeycomb ceramics as the catalyst carrier, and the surface of the catalyst carrier is coated with two layers of coatings containing noble metals Pd and Rh, including a primer coating and an outer coating, wherein the primer coating includes Pd‑Sr/La‑Al 2 O 3 powder and Pd/Ce‑Zr solid solution powder are mixed to form a slurry, and additives and binders are added to coat the catalyst carrier to form a bottom coating; the outer coating includes Rh/Zr‑ Nb-Al 2 O 3 powder and Pd/Ce-Zr solid solution powder, by modifying zirconium-doped alumina, a small amount of acidic oxide is loaded on the zirconium-doped alumina, which can increase the acid sites on the surface of alumina, It is conducive to the generation of reduced Rh and inhibits the generation of oxidized Rh. The invention improves the light-off and durability performance of the existing TWC catalyst, improves the low-temperature light-off activity of hydrocarbons, CO and NOx , and has better durability of the catalyst. |