Layered double hydroxide, role

As mentioned previously, the role of the metal is not specific. Even transition metal free layered double hydroxides are suitable catalysts for the olefin epoxidation with O2 and a sacrificial aldehyde (205). Leaching of the metal from the solid catalyst is a serious problem since organic acids that are potential metal ligands accumulate during the reaction. Leaching occurs, for example, with the polybenzimidazole-supported Ni2+ catalyst (199). 

FIGURE 2.96 Illustrations of the roles of hexacyanoferrate (II) and (III) in the courses of charge (a) and discharge (b) for the Co-Al LDH electrode. (Su, L. H. et al. 2009. Improvement of the capacitive performances for Co-Al layered double hydroxide by adding hexacyanoferrate into the electrolyte. Physical Chemistry Chemical Physics 11 2195-2202. Reproduced by permission of The Royal Society of Chemistry.)... 

Palmer S. J., Frost R. L. and Nguyen T. (2009), Hydrotalcites and their role in coordination of anions in Bayer liquors Anion binding in layered double hydroxides . Coord. Chem. Rev., 253,250-67. 

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