Structure and surface chemistry of manganese-doped copper-based mixed metal oxides derived from layered double hydroxides

Abstract

The paper reports data relative to the preparation of a series of manganese-doped copper-based mixed metal oxides under identical conditions by calcination of layered double hydroxides (LDHs) at 773 K for 5 h. LDHs with Cu 2+/Zn 2+/Mn 2+/Fe 3+/Al 3+ molar ratios in synthesis mixture from 1:1:0:0.3:0.7 to 1:0:1:0.3:0.7 have been synthesized by co-precipitation method. The samples of both the as-synthesized LDHs and the corresponding calcined LDHs have been characterized for phase composition by powder X-ray diffraction (XRD), FT-IR spectroscopy and chemical analysis. The calcined LDHs were submitted to X-ray photoelectron spectroscopy (XPS) investigation with the aim of assessing the actual elemental speciation on the surface of the materials from the analysis of the M 2p (M = Cu, Mn, Fe and Al), Cu 3p and O1s spectral regions. Calculating the relative intensities of spectral components to determine the distributions of different chemical states has been performed by the fitting procedure of the experimental XPS peaks, and significant changes were noted when the partial substitution of manganese for zinc is increased.