Pd-Doped Perovskite: An Effective Catalyst for Removal of NOx from Lean-Burn Exhausts with High Sulfur Resistance

Herein, we report the Pd-doped perovskite La0.7Sr0.3CoO3 as an effective lean NOx trap (LNT) catalyst. This smart perovskite displays excellent NOx reduction activities for lean-burn exhausts (NOx conversion >90%, N2 selectivity >90%) over a wide operating temperature range (275–400 °C), as well as an extremely high sulfur tolerance. Our results evidenced Pd dissolving into or segregating out of perovskite in lean-burn and fuel-rich atmospheres. The segregated metallic Pd from perovskite in fuel-rich atmospheres is crucial for obtaining these promising achievements. These findings provide a new possibility for the application of the Pd-based LNT catalysts.