Structural and synergistic effects of three-dimensionally ordered macroporous Ce0.8Zr0.2O2-supported Pt nanoparticles on the catalytic performance for soot combustion

Three-dimensionally ordered macroporous (3DOM) Ce0.8Zr0.2O2-supported Pt catalysts were firstly synthesized. All the materials possess well-defined 3DOM nanostructure and highly dispersed Pt nanoparticles on the inner walls of uniform macropores. 3DOM structure improves the contact efficiency between catalyst and soot, and the metal (Pt)–support (Ce) synergistic effect increases the amount of active oxygen species. 3DOM Ptn/Ce0.8Zr0.2O2 catalysts exhibited high catalytic activity and thermal stability for soot combustion. The structural and synergistic effects of 3DOM Ptn/Ce0.8Zr0.2O2 catalysts are favorable for weakening the NOx constrain on the catalytic activity, e.g., the ΔT50 of 3DOM Pt4/Ce0.8Zr0.2O2 catalyst is only 60 °C, while that of Pt4/Ce0.8Zr0.2O2-particles catalyst is 105 °C. The reaction pathways for catalyzing soot combustion can be divided into two parts: one is that active oxygen species directly oxidize soot particles; the other one is that NO2 acts as an intermediate to catalyze soot oxidation.

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► 3DOM Ptn/CZ catalysts were firstly synthesized by GBMR method.
► The catalysts exhibited super catalytic activities and stability for soot combustion.
► The soot combustion process over 3DOM catalyst was observed by “in situ” TEM images.
► 3DOM structural effect is favorable for weakening the dependence of catalytic activity on NOx.
► Structural and synergetic effects of 3DOM and Pt nanoparticles were systematically investigated.