硝酸盐溶液浓度对镁铝水滑石结构记忆效应的影响

Influence of nitrate solution concentration on the memory effect of Mg-Al hydrotalcite

用共沉淀法制备了镁铝水滑石,并进行XRD、N2吸附-脱附、TG-DTA和FT-IR等表征。结果表明,制备的镁铝水滑石呈六方晶型,比表面积为121 m2.g-1。研究了硝酸盐溶液浓度对水滑石结构记忆性的影响,发现400℃焙烧5 h的镁铝水滑石在硝酸铜和硝酸铁溶液中浸泡可以恢复水滑石结构,溶液浓度越低越容易恢复,同时NO3-插入水滑石的层间可以形成一种新型应用功能材料。

Mg-Al hydrotalcite was prepared by coprecipitation method and characterized by XRD, N2-adsorption-desorption,TG-DTA and FT-IR. The results showed that the as-prepared Mg-Al hydrotalcite with 121 m^2·g^-1 specific surface area possessed hexagonal phase. The influence of nitrate solution concentration on the memory effect of Mg-Al hydrotalcite was investigated. It was found that Mg-Al mixed oxides formed after being calcined at 400 ℃ for 5 h was dipped in different concentration of Cu （ NO3 ） 2 and Fe （ NO3 ） 3 aqueous solution. The hydrotalcite structure could be recovered and the memory effect of hydrotalcite was influenced by salt solution concentration. Furthermore, the lower concentration was more advantageous to the recovery of hydrotalcite structure. The results of FT-IR demonstrated that the insertion of NO3 in the layer of hydrotalcite could be observed,which might form a new type application function material.