Effect of K loadings on nitrate formation/decomposition and on NOx storage performance of K-based NOx storage-reduction catalysts

- K2O/Al2O3 and Pt-K2O/Al2O3 with varying K loadings were prepared.
- K2O(20)/Al2O3 formed more thermally stable nitrate species than K2O(10)/Al2O3 upon NO2 adsorption.
- Temperature of max. NOx uptake shifted from 573 K to 723 K with increasing K loadings from 10 wt% to 20 wt%.
- Moreover, the efficiency of K for storing NOx increased more than three times.