Chromium and yttrium-doped magnesium aluminum oxides prepared from layered double hydroxides

Yttrium promoted Ni-based double-layered hydroxides for dry methane reforming

“…The c' parameter, equal to one brucite-like sheet and one interlayer (c´=c/3), is 7.8 Å and constant for our HTNi-Y catalysts, indicating the presence of CO 3 2anions in the samples (7.65 Å) [19]. Finally, the lattice parameter a is also stable for all catalysts (3.06 Å), although García-García et al [54] assumed that the introduction of yttrium into DLHs layers, considering its ionic radius bigger than that of Mg and Al (Y 3+ =1.04 Å, Mg 3+ =0.86 Å, Al 3+ =0.675 Å) [55], may cause lattice distortions, i.e. changes in the lattice parameter a.…”

Fluorine-Modified Mesoporous Ni–Mg–Al Mixed Oxides for Partial Oxidation of Methane

“…3). The XRD patterns showed the formation of a NiO-MgO periclase type with peaks at about 38°, 43°a nd 63°, respectively [15][16][17]. Moreover, the phase of orthorhombic magnesium aluminum oxides MgAl 2 O 4 (PDF no.…”

“…Furthermore, various basic elements were added to reduce carbon deposition as well as sintering [9][10][11][12]. Nevertheless, alkali oxides were not stable under hard reaction condition due to their water-solubility, and the incorporation of alkali earth (except for Mg) and rare earth elements into nickel-containing catalyst matrix was difficult due to their larger differences in the electronegativity and ionic radii with that of nickel [13][14][15][16][17]. Thus, anion-modified Ni-Mg-Al mixed oxides were explored in the present work.…”

A Family of Visible‐Light Responsive Photocatalysts Obtained by Dispersing CrO6 Octahedra into a Hydrotalcite Matrix

“…4 T 2g (F) of Cr 3 + , respectively, in an ordered octahedral environment in the LDH layer. [23][24][25] The MCr À CO 3 -LDH samples also show similar absorption maxima at 410 and 570 nm ( Figure S3 in the Supporting Information). The small shift in the absorption band for these LDH materials might be due to the electronic competition among Cr III and the M II metal ions.…”