Experimental investigation of sheet flexibility of layered double hydroxides: One-pot morphosynthesis of inorganic intercalates

The sheet flexibility of layered double hydroxides (LDHs) has been investigated experimentally using coprecipitation and urea hydrolysis methods in an aqueous solution of long-chain anion surfactant in this work. Using dodecylsulfate (DS) anion as morphology-controlling agent, layer-bended or contorted Mg/Al-LDH is obtained successfully. The morphology of bent layers is retained during either in situ decomposition of interlayer DS to SO42- or ion exchange of interlayer DS by CO32-. The direct synthesis of the layer-distorted LDHs intercalated with small inorganic anions is quite difficult. It has been achieved using layer-bended LDHs pillared with bulky organic anions as precursors in this paper. The morphosynthesis is expanded to Co/Al and Ni/Al-LDHs, indicative of the general flexibility of this kind of anionic clays. (C) 2008 Elsevier B.V. All rights reserved.