CO Management for Hydrogen Processes Through a Catalytic Oxidation Mechanism on Dual-Doped Perovskites with Tuned Co and Ni Ratios

In hydrogen processes, managing CO emissions and removal by catalytic oxidation is crucial during H2 production, storage/transportation, and use, ensuring the efficiency and safety of hydrogen systems and contributing to more sustainable energy solutions. Perovskite-structured transition metal oxide catalysts have been widely studied in various energy and environmental applications due to their extensive compositional modifications and electronic adjustments, facilitating catalytic behavior. Here, Ce-based perovskite catalysts with dual active metal doping at varying Co and Ni ratios are investigated to understand their structural and redox properties in CO oxidation. The reaction mechanism involves CO adsorption, oxygen activation, and redox cycling, confirming catalytic turnover. In situ DRIFTS analysis reveals real-time surface transformations with catalytic activity, which vary with Co and Ni doping ratio. Relatively, CO adsorption on Co3+ dominates the low-temperature activity, whereas Ni contributes to the efficiency at elevated temperatures. LCCNTxy (La0.7Ce0.1CoxNiyTi0.6O3) with x = 0.3 and y = 0.1 exhibits the highest performance, achieving T10 above 40 °C and the fastest T90 at 230 °C. This study highlights the compositional tuning in dual-doped perovskites and complementary roles of Co and Ni in CO oxidation for developing efficient industrial catalysts.