The carrier effect of ternary solid solution derived by trimetallic CeZrNi MOFs on the Pd dispersion stability for NGVs exhaust purification

Abstract

This article was the first to prepare CeZrNiOx ternary solid solution using CeZrNi BDC MOFs as a template, and investigate its effect on improving the dispersion stability of Pd components in three‐way catalysts and the catalytic performance of natural gas exhaust purification. The experimental results indicated that CeZrNiOx derived from CeZrNi‐BDC MOFs had a stable solid solution uniform structure and relatively good thermal stability of the porous structure. Therefore, the thermal stability of Pd/CZN‐M derived from CeZrNi BDC MOFs was significantly better than that of Pd/CZN‐C prepared by citric acid complexation method. The PdO particle size of Pd/CZN‐M before and after thermal aging was only about 2.0 and 4.5 nm, respectively. At GHSV50000 ml/(g·h), the T90 of aged Pd/CeZrNiOx for CH4, NO, and CO reached 410, 370, and 175 oC, respectively, showing better three‐way catalytic (TWC) activity than reported in existing literature. In addition, CeZeNiOx carriers derived from MOFs also enhanced the co‐activation ability of NO and CH4, and exhibited certain activity in the low‐temperature self‐decomposition reaction of NO, thus showing significant advantages in the TWC catalytic activity of NGVs. This work would provide a new method for preparing NGVs exhaust TWC catalysts with high dispersion stability.