Decomposition pathways of hydrotalcite-like compounds Mg1-xAlx(OH)2(NO3)x.nH2O as a continuous function of nitrate anions
Decomposition pathways of hydrotalcite-like compounds Mg1-xAlx(OH)2(NO3)x.nH2O as a continuous function of nitrate anions
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DOI：
10.1021/cm010347g
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发表时间：
2001-10
影响因子：
8.6
通讯作者：
Z. Xu;H. Zeng
中科院分区：
文献类型：
--
作者：
Z. Xu;H. Zeng
采用XRD、DTA、TGA、FTIR和TGA/FTIR联用技术研究了我们最近制备的类水滑石化合物Mg 1-xAlx（OH）2（NO3）x·nH 2 O（x = 0.20−0.34）（J. Phys. Chem. B 2001，105，1743−1749）的热分解途径。研究发现，与碳酸化水滑石不同，低硝酸根含量（x）的水滑石中阴离子的脱羟基和分解是分离的，而高硝酸根含量（x）的水滑石中这两个过程是重叠的。根据我们最近的结构模型，具有高x值的样品中的脱羟基过程可以进一步区分为步骤，这取决于羟基的化学性质和硝酸盐含量。当更多的硝酸根离子插入时，这些水滑石化合物的层状结构变得更热稳定。低x化合物中硝酸根阴离子（分解为NO2和O2）的消耗是一个连续过程，而高x化合物中硝酸根阴离子的消耗是一个离散过程。在400 °C下，大多数硝酸根阴离子都是...
Thermal decomposition pathways of our recently prepared hydrotalcite-like compounds Mg1-xAlx(OH)2(NO3)x·nH2O in x = 0.20−0.34 (J. Phys. Chem. B 2001, 105, 1743−1749) have been investigated with XRD, DTA, TGA, FTIR, and combined TGA/FTIR techniques. It has been found that, unlike those in carbonated hydrotalcites, the dehydroxylation and decomposition of anions in low nitrate-content (x) hydrotalcites are separated, while the two processes in the high x samples are overlapped. In line with our recent structural models, the dehydroxylation process in the samples with high x value can be further differentiated into steps, depending on chemical nature of hydroxyl group and nitrate content. The layered structure of these hydrotalcite compounds becomes thermally more stable when more nitrate ions are intercalated. The depletion of nitrate anions (decomposed into NO2 and O2) in the low x compounds is a continuous process, whereas that in the high x compounds is a discrete one. At 400 °C, most nitrate anions are ...