Tuning Perovskite Catalysts for Dry Reforming of Methane via Strontium Doping

Dry reforming of methane (DRM) is a promising approach for syngas production, utilizing CO₂ as a reactant to mitigate greenhouse gas emissions and enhance sustainability. Despite its potential, DRM faces significant challenges, including the high temperatures required and catalyst deactivation due to coking and sintering. Perovskite-based catalysts, particularly those doped with transition metals and alkaline earth elements, have emerged as effective solutions due to their structural stability, tunable electronic properties, and ability to disperse active metals uniformly. In this study, the catalytic performance of La_ySr_1-yNi_0.5Mg_0.5O₃ perovskites with varying Sr substitution levels (y = 0.2, 0.4, 0.5, 0.6, 0.8) was investigated for DRM. The catalysts were synthesized via solution combustion synthesis (SCS) and characterized by their ability to enhance CO₂ and CH₄ conversions. The results demonstrated that Sr substitution significantly influenced catalyst performance by altering structural properties, oxygen mobility, and basicity. Catalysts with higher Sr content exhibited improved CO₂ adsorption and activation at lower temperatures, while La-rich samples showed enhanced stability and activity at elevated temperatures. Notably, the y = 0.8 sample achieved the highest CO₂ and CH₄ conversions (80% and 70%, respectively) at 750 °C. These findings underline the synergistic roles of Sr and La in optimizing the catalytic behavior for DRM, providing insights into the design of efficient and stable catalysts. By advancing our understanding of perovskite modifications, this work contributes to the development of sustainable technologies for CO₂ utilization and greenhouse gas reduction.