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采用水浴液中阴离子直接交换法合成了具有不同钒含量的Ｋｅｇｇｉｎ结构磷钨钒杂多阴离子ＰＷ（１２－ｎ）ＶｎＯ（４０）（ｎ＝１—５）柱撑水滑石，用元素分析、ＸＲＤ和ＩＲ对柱撑产物的组成和结构进行了表征．ＸＲＤ结果给出柱撑产物的底面间距达１．４７Ｍ．ＤＴＡ结果表明柱撑产物的热稳定性高于水滑石前驱体，且与杂多阴离子中Ｖ含量相关．由不同温度下焙烧样品的ＸＲＤ和ＩＲ研究可知，柱撑产物的热分解过程为：＜２５０℃时脱除物理吸附水和层间水；２５０～４００℃范围内脱羟基（同时伴随着层间Ｋｅｇｇｉｎ离子结构的破坏）；４００℃以上生成ＷＯ３和Ｍｇ２Ｖ２Ｏ７，后者在７５０℃以上分解为ＭｇＯ和Ｖ２Ｏ５．
The Keggin-structured heteropolyphosphoric tungsten-vanadium heteropolyanions PW (12-n) VnO (40) (n = 1-5) with different vanadium contents were synthesized by anionic direct exchange method in water bath. The elemental analysis, XRD And IR were used to characterize the composition and structure of the pillared product. XRD results show that the pillaring product has a bottom spacing of 1.47M. The DTA results show that the thermal stability of the pillared product is higher than that of the hydrotalcite precursor and is related to the V content in the heteropolyanion. According to the XRD and IR studies of calcined samples at different temperatures, the pyrolysis process of the pillared product is: physical adsorption of water and interlayer water at <250 ° C; dehydroxylation at 250-400 ° C (accompanied by interlayer Keggin ion structure damage); above 400 ℃ to generate WO3 and Mg2V2O7, the latter above 750 ℃ decomposition of MgO and V2O5.