This work investigated the performance of supported LaNiO₃ perovskite-type oxides for the CO₂ reforming of methane. The methane and CO₂ conversion increased at the beginning of reaction for LaNiO₃ and LaNiO₃/Al₂O₃ catalysts. On the other hand, conversion remained quite constant for LaNiO₃/CeSiO₂. in situ XPS experiments under reaction conditions revealed that the metallic Ni particles were oxidized by CO₂ from the feed for LaNiO₃ and LaNiO₃/Al₂O₃ catalysts. Ceria support was preferentially oxidized, limiting the oxidation of the metallic phase. Raman spectroscopy and thermogravimetric analysis showed that carbon was formed mainly over LaNiO₃ and LaNiO₃/Al₂O₃ catalysts. Supporting LaNiO₃ over CeSiO₂ almost completely suppressed carbon deposition. in situ XPS experiments showed a continuous change of ceria oxidation states between Ce⁴⁺ and Ce³⁺ under reaction conditions. This result in a high oxygen mobility of ceria support that reacts with carbon, inhibiting the formation of nickel carbide and consequently the nucleation and growth of carbon filaments.

中文翻译：

---

负载型LaNiO ₃钙钛矿型氧化物上甲烷的CO ₂重整

这项工作研究了负载的LaNiO ₃钙钛矿型氧化物对甲烷CO ₂重整的性能。对于LaNiO ₃和LaNiO ₃ / Al ₂ O ₃催化剂，在反应开始时甲烷和CO ₂转化率增加。另一方面，LaNiO ₃ / CeSiO _2的转化率保持相当恒定。反应条件下的原位XPS实验表明，金属Ni颗粒被LaNiO ₃和LaNiO ₃ / Al ₂ O ₃进料中的CO ₂氧化催化剂。二氧化铈载体被优先氧化，限制了金属相的氧化。拉曼光谱和热重分析表明，碳主要在LaNiO ₃和LaNiO ₃ / Al ₂ O ₃催化剂上形成。在CeSiO ₂上负载LaNiO ₃几乎完全抑制了碳沉积。原位XPS实验表明Ce ⁴⁺和Ce ³⁺之间二氧化铈氧化态的连续变化在反应条件下。这导致二氧化铈载体的高氧迁移率，其与碳反应，抑制了碳化镍的形成，从而抑制了碳丝的成核和生长。