Carbon deposition is the main cause for the catalyst deactivation of methane dry reforming, and researchers are committed to exploring effective catalyst systems with zero carbon deposition in order to achieve a practically long lifetime. In this work, we propose an equilibrium theory with matched rates of CH₄ dissociation and CO₂ activation to establish a balance between carbon deposition and carbon elimination and construct highly dispersed Ni-Ir/MgAl₂O₄ alloy catalysts accordingly, where Ni activated CH₄, MgAl₂O₄ adsorbed CO₂ to form surface carbonates, and Ir effectively used the carbonates to eliminate carbon species generated by CH₄ dissociation. Theoretical assessment further unveiled that the preferred CO₂ activation on Ir over Ni is derived from its stronger oxophilicity. With an optimal Ni/Ir atomic ratio of 1/2, high activity and long-period stability (600 h) with zero carbon deposition were obtained concurrently for dry reforming of methane at industrially relevant temperature (650°C).

碳沉积是甲烷干法重整催化剂失活的主要原因，研究人员致力于探索零碳沉积的有效催化剂体系，以实现长寿命。在这项工作中，我们提出了一种与 CH ₄解离和 CO ₂活化速率相匹配的平衡理论，以建立碳沉积和碳消除之间的平衡，并相应地构建高度分散的 Ni-Ir/MgAl ₂ O ₄合金催化剂，其中 Ni 活化 CH ₄、MgAl ₂ O ₄吸附CO ₂形成表面碳酸盐，Ir有效地利用碳酸盐消除CH ₄解离产生的碳物质。理论评估进一步揭示了 Ir 上的 CO ₂活化优于 Ni 源于其更强的亲氧性。在最佳 Ni/Ir 原子比为 1/2 的情况下，在工业相关温度（650°C）下甲烷干重整同时获得高活性和长期稳定性（600 h），零碳沉积。