Modulating the active phase in perovskite LaCoO3 with B-site doping of Cu for efficient methanol reforming to produce hydrogen

Abstract

Optimizing methanol reforming for hydrogen production is crucial, in which the regulation of the catalyst structure has a significant impact on improving catalytic activity. LaCoO₃ perovskite is a promising catalyst for this application due to its tunable structure and exceptional thermal stability. This work reports the modulation of the active phase in the perovskite LaCo_1−xCu_xO₃ (x = 0, 0.03, 0.06, 0.12) by annealing under a H₂ atmosphere. The results of XPS, XRD, and H₂-TPR reveal that Cu doping and hydrogen reduction can modify the chemical states of B-site elements. Consequently, the activity of methanol reforming for hydrogen production is considerably enhanced. The optimal performance for methanol hydrogen production observed in LaCo_0.97Cu_0.03O₃ suffered from H₂ reduction at 300 °C. This is due to the modulation of the active phase structure with appropriate redox pairs of Cu²⁺/Cu⁺, Co³⁺/Co²⁺ and O²⁻/O_v. This work offers valuable insights in the development of efficient catalysts for methanol reforming and hydrogen production.