Cu-Ni-Mg-Al-CO3四元水滑石的合成及结构分析

以Cu(NO3)2·2H2O,Ni(NO3)2·6H2O,Mg(NO3)2·6H2O和Al(NO3)3·9H2O为原料 ，以NaOH和Na2CO3为沉淀剂，采用成核／晶化隔离法合成了Cu-Ni-Mg-Al-CO3四元 水滑石，通过XRD，FT－IR，TG－DTA，ICP等手段对样品进行测试和表征，并且对 水滑石结构的层板和层间阴离子相互作用进行分析和讨论。结果表明，控制Cu^2+ 离子与其它二价金属离子的配比，可制备晶体结构规整的M(Ⅱ）4M(Ⅲ)2(OH) 12CO3·4H2O型水滑石；Cu^2+离子的引入导致了明显的Jahn-Teller效应；且随 Mg^2+量的增加，使得这种效应更加显著，另一方面Mg^2+量的增加有利于Cu-Ni- Mg-Al-CO3四元水滑石晶体在a方向上生长，增强其热稳定性。

Synthesis and Structural Analysis of Cu-Ni-Mg-Al-CO3 Hydrotalcite-like Materials

Cu-Ni-Mg-Al-CO_3 hydrotalcite-like materials have been synthesized at high supersaturation using a new method developed in our laboratory by combining a mixed solution of Cu(NO_3)_2·6H_2O, Mg(NO_3)_2·6H_2O and Al(NO_3)_3·9H_2O with a second solution containing NaOH and Na_2CO_3. The materials obtained have been characterized by XRD, FT-IR, TG-DTA and ICP. The influence of different molar ratios of divalent metal ions on the crystal structure, selectivity of crystal growth in different directions and host-guest interactions in the Cu-Ni-Mg-Al- CO_3 hydrotalcite-like materials has been investigated. It is shown that Cu-Ni-Mg-Al-CO_3 hydrotalcite-like nanomaterials can be obtained using this method, and the influence of the Jahn-Teller effect on the crystal structure, thermal stability and host-guest interactions because of the presence of Cu~(2+) is quite marked. Furthermore, with increasing amounts of Mg~(2+), the thermal stabilities of Cu-Ni-Mg-Al- CO_3 hydrotalcite-like materials become better.