Simultaneous incorporation of palladium and zirconium ions in Mg-Al layered double hydroxides by co-precipitation

Simultaneous incorporation of palladium and zirconium ions in Mg-Al layered double hydroxides (LDHs) was attempted by co-precipitation. Mixed oxides were obtained by calcination at 500 degrees C. XRD patterns of as-synthesized samples showed the formation of well-crystallized LDHs at lower Zr contents. The CO(3)(2-) content of the solids has been determined to have information on the possible incorporation of Zr(4+) into the brucite layer of the hydrotalcites. The values obtained showed that Zr(4+) can incorporate into brucite sheets at Zr content lower than 10 mon. SEM and TEM images indicated that the resulted LDHs with lower Zr content exhibited plate-like structure. Thermal calcination at 500 degrees C results in the formation of mixed oxides containing MgO, PdO, ZrO(2) crystallites and a solid solution formed by some of the Zr(4+) cations dissolving along with Al(3+) to MgO lattice. (C) 2011 Elsevier B.V. All rights reserved.