Influence of element doping on La–Mn–Cu–O based perovskite precursors for methanol synthesis from CO2/H2

Abstract

Doped La–M–Mn–Cu–O based (M = Ce, Mg, Y, Zn) perovskite materials were prepared by the sol–gel method and characterized by XRD, N₂-adsorption, ICP-OES, SEM, TPR, N₂O-adsorption, XPS and TPD techniques. Upon the introduction of the fourth elements, all the samples keep the stable LaMnO₃ perovskite structure, and part of the copper species is separated from the perovskite lattice. More structure defects, lower reduction temperature and better low-temperature H₂ adsorption on the unit surface area are observed. In the application for methanol synthesis from CO₂/H₂, the Zn doped catalyst showed better performance which may because the strength of the weak basic sites play a significant role on methanol selectivity and the amount of H₂ adsorbed on the unit surface area is the key for CO₂ conversion.