Dual-Active-Sites in Co-Doped Pd/Beta Catalyst for Robust Soot Oxidation

The development of robust catalysts for soot oxidation is crucial for the emission control of diesel vehicles. Herein, a 0.5%Pd-1%Co/Beta catalyst with extraordinary soot oxidation activity is developed by doping Co into 0.5%Pd/Beta. Remarkably, doping with Co reduced the T₅₀ of 0.5%Pd/Beta by 69 °C, surpassing even the activity of 1%Pd/Beta. Experiments and DFT (density functional theory) calculations identified that Co doping induces the formation of dual-active-sites in the Pd-Co/Beta catalyst (Pd^δ+ (0 < δ < 2) species and oxygen defects), which are beneficial for the adsorption/activation of reactants (O₂ and NO) and dissociation of the intermediate (NO₂), ultimately leading to more NO₂ participating in soot oxidation. This study presents a strategy to enhance the soot oxidation activity of noble metal catalysts while simultaneously reducing the amount of noble metal used. The developed 0.5%Pd-1%Co/Beta catalyst is a promising candidate for soot control on diesel vehicles.