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

Abstract

Doped perovskites possess better structure properties, the catalytic performance depends on the behaviour of the reactants.

Copper-based Perovskite Design and Its Performance in CO2 Hydrogenation to Methanol

“…In all diffraction patterns, no phase that ascribes to Mg, Y, or Zn is observed, while a new phase ascribed to CeO 2 is found for the sample of Ce-P, which demonstrates that it is difficult for all the Ce to enter the perovskite lattice, which agrees with the conclusion by Weng et al [18]. The physicochemical properties of the calcined perovskite-type catalysts are summarized in Table 1 [17]. Low specific surface area for perovskite-type oxides is common.…”

“…The XPS results presented in Table 2 [17] show that lanthanum ions of the reduced perovskitetype catalysts are present in the trivalent form because the La 3d5/2 peak is close to the value of pure lanthana at 834.4 eV [20]. However, the BE of La 3d5/2 of P sample is higher than the other samples, which implies the increasing of the electron cloud density around La ions for the doped samples.…”

“…Two CO 2 desorption peaks are observed for all samples (Figure 3), which are denoted as peak α and peak β [17]. The peak α at around 400 K could be assigned to weak basic sites and the peak β at around 600 K could be assigned to strong basic sites.…”

“…As shown in Figure 1a [17], for the La-M-Mn-Cu-O (M = Mg, Y, Zn, Ce) based perovskite precursors, the LaMnO 3 (JCPDS # 75-0440) are the main phase. The diffraction peak at about 2θ=32.5° shift towards higher values when the fourth elements were doped.…”

“…The presence of surface adsorbed oxygen species suggests the formation of oxygen vacancies in the defected oxides [23] (917.9 eV) [19,28]. The Auger electron spectroscopies of Cu LMM of reduced samples are shown in Figure 2 [17]. The profiles are convoluted into two peaks.…”