Ce-Pr Co-doped Co3O4 with Enriched Oxygen Vacancies for the Efficient Decomposition of N2O

Abstract

Nitrous oxide (N₂O) has gained increasing attention as a non-carbon dioxide greenhouse gas, and catalytic decomposition is an effective method for mitigating its emissions. In this study, Ce-Pr Co-doped Co₃O₄ was synthesized via a coprecipitation method and used for the catalytic decomposition of N₂O. The experimental results revealed that the N₂O decomposition achieved 100% conversion at 400 °C on the catalyst with a Pr/Ce/Co molar ratio of 0.02:0.2:1, exhibiting an 80 °C decrease of T₁₀₀ compared with that of Co₃O₄. The introduction of Ce reduced the size and crystallization of Co₃O₄ particles, increased the activity of the lattice oxygen of Co₃O₄, and facilitated the formation of oxygen vacancies, thereby enhancing the activation of N₂O. However, the introduction of Ce inhibited the crystallization of Co₃O₄ and the surface coverage of CeO₂ decreased the exposure degree of N₂O molecules to the Co₃O₄ surface. Co-doping strategy of Ce-Pr was performed to alleviate the negative effects of ceria. Consequently, the incorporation of Ce and Pr species enhanced the redox properties of Co₃O₄, leading to remarkable catalytic performance of N₂O decomposition. This study elucidated the interaction between Ce and Pr dopants and Co₃O₄, and encouraged more attention on designing novel catalysts for N₂O mitigation.