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Ni nanoparticles encapsulated within La₂O₃ porous system (Ni@La₂O₃), the latter supported on SiO₂ (Ni@La₂O₃)/SiO₂), effectively inhibit carbon deposition for the dry reforming of methane. In this study, Ni@La₂O₃/SiO₂ catalyst was prepared using a one-pot colloidal solution combustion method. Catalyst characterization demonstrates that the amorphous La₂O₃ layer was coated on SiO₂, and small Ni nanoparticles were encapsulated within the layer of amorphous La₂O₃. During 50 h of dry reforming of methane at 700 °C and using a weight hourly space velocity (WHSV) of 120,000 mL g_cat^−1 h^−1, the CH₄ conversion obtained was maintained at 80%, which is near the equilibrium value, while that of impregnated Ni−La₂O₃/SiO₂ catalyst decreased from 63% to 49%. The Ni@La₂O₃/SiO₂ catalyst exhibited very good resistance to carbon deposition, and only 1.6 wt% carbon was formed on the Ni@La₂O₃/SiO₂ catalyst after 50 h of reaction, far lower than that of 11.5 wt% deposited on the Ni−La₂O₃/SiO₂ catalyst. This was mainly attributed to the encapsulated Ni nanoparticles in the amorphous La₂O₃ layer. In addition, after reaction at 700 °C for 80 h with a high WHSV of 600,000 mL g_cat^−1 h^−1, the Ni@La₂O₃/SiO₂ catalyst exhibited high CH₄ conversion rate, ca. 10.10 mmol g_Ni^−1 s^−1. These findings outline a simple synthesis method to prepare supported encapsulated Ni within a metal oxide porous structure catalyst for the dry reforming of methane reaction.