CeNiO₃ perovskite nanoparticles synthesized using gelatin as a chelating agent for CO₂ dry reforming of methane

CeNiO₃ perovskite nanoparticles were synthesized using gelatin as a chelating agent to catalyze the CO₂ dry reforming reaction. The optimization of gelatin concentration affects the formation of Ni coordinated on the B-sites of CeNiO₃. CeNiO₃ shows catalytic stability for 60 h with ∼50% CO₂/CH₄ conversion and a H₂/CO ratio of ∼0.8 when obtained using low concentrations of gelatin (0.05 g, 0.1 g). The exsolution of Ni nanoparticles from CeNiO₃ structures occurs during reduction treatment, expanding the crystal lattices of CeO₂. A high gelatin concentration (0.2 g) reduced Ni mobility and restricted Ni-Ce contacts. The uncoordinated Ni in CeNiO₃ exposes a high surface area (10.12 m² g⁻¹) for CH₄ dissociation, consequently increasing the H₂/CO ratio to ∼1.5 with 78% CH₄ and 53% CO₂ conversion. In situ DRIFTS analysis showed that CH₄ readily dissociates in the absence of CO₂, but CO₂ completes the reaction cycles by removing the carbon as CO gas.