微波场下纳米Mg-Al-LDHs及PO_4~(3-),P_2O_7~(4-)柱撑Mg-Al层状双氢氧化物的合成

用微波加热反应-变速滴加共沉淀法合成了[Mg-Al-CO3]纳米层状双氢氧化物,并以[Mg-Al-CO3]纳米层状双氢氧化物为前体,用微波加热反应-离子交换法制备了PO43-,P2O74-柱撑Mg-Al层状双氢氧化物。该法合成的[Mg-Al-CO3]纳米层状双氢氧化物的粒径约为10-40nm。讨论了微波和变速滴加碱液的速度对纳米层状双氢氧化物的合成的影响。用FT-IR、TEM与XRD对产物进行了表征,结果表明在微波加热反应的条件下可在短时间内用PO43-,P2O74-彻底交换CO32-。

Syntheses of Nanocrystalline Mg-Al-LDHs and PO_4~(3-), P_2O_7~(4-) Anion-Pillared Layered Double Hydroxides under the Conditions of Microwave

Nanocrystalline [Mg-Al-CO3] layered double hydroxides were prepared by using microwave irradiation and varied rate of dripping alkali. Then [Mg-Al-PO4 and [Mg-Al-P2O7] layered double hydroxides were successfully synthesized by the direct reaction of free PO43- and P2O74-with [Mg-Al-CO3] layered double hydroxides precursor using microwave technique and the anion-intercalation method. By using this method [Mg-Al-CO3] layered double hydroxides with a particle size of about 10nm to 40nm were produced. The effect of microwave and the rate of dripping alkali on [Mg-Al-CO3] layered double hydroxides was discussed. And the samples thus obtained were characterized by FT-IR, TEM and XRD. The results show that the initial interlayer carbonate ions can be completely replaced by PO43- and P2O74- under the controlled microwave conditions employed in a short time.