Zhao Lina, Xu Ting, Lei Xiaodong, Xu Sailong, Zhang Fazhi
State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
J Nanosci Nanotechnol. 2011 Apr;11(4):3291-7. doi: 10.1166/jnn.2011.3739.
Layered double hydroxides (LDHs), also known as hydrotalcite-like layered clays, have previously been investigated as a potential solid alkaline catalyst. A necessary calcinations/rehydration procedure, however, is utilized to enhance surface area and catalytic activity of LDHs involved. Here we report on a scalable preparation of sodium alginate-templated MgAI-LDH (LDH/SA) mesoporous composites with high surface area and surface acidity. The powdery LDH/SA mesoporous composites are prepared using alginate as template by a scalable method of separate nucleation and aging steps (SNAS). Comparison with the pristine MgAl-LDH shows that the obtained LDH/SA composites exhibit the greatly enhanced surface area and surface activity of surface acid sites at the elevated high temperatures which have scarcely been reported previously. Our results may allow designing a variety of mesoporous LDH-containing composites with potential applications in specific catalysis and purification processes.
层状双氢氧化物（LDHs），也被称为类水滑石层状粘土，此前已被研究作为一种潜在的固体碱性催化剂。然而，需要进行煅烧/再水化程序来提高所涉及的LDHs的表面积和催化活性。在此，我们报告了一种可扩展制备具有高表面积和表面酸度的海藻酸钠模板化MgAl-LDH（LDH/SA）介孔复合材料的方法。通过一种可扩展的单独成核和老化步骤（SNAS）方法，以海藻酸盐为模板制备了粉末状的LDH/SA介孔复合材料。与原始的MgAl-LDH相比，所获得的LDH/SA复合材料在高温下表现出大大增强的表面积和表面酸性位点的表面活性，这在以前几乎没有报道过。我们的结果可能有助于设计各种含介孔LDH的复合材料，在特定的催化和净化过程中具有潜在应用。
