纳米晶Mg-Al水滑石的水热合成及晶粒度调控

Hydrothermal synthesis of nano Mg-Al LDHs of controllable aspect ratio

以水不溶性的化合物为前驱物，水热法一步合成了纳米晶Mg-Al水滑石。用XRD、SEM和FT-IR对合成产物进行了表征。通过系统分析前驱物类型、反应温度、时间和碱度与水热反应产物物相组成和晶粒度的关系，提出了调控Mg-Al水滑石晶粒度的方法：升高温度、延长反应时间、适度提高碱度，均会使晶粒度均匀增大。其它条件相同时，前驱物间的竞争性水解能力是影响物相纯度和晶粒度的主要因素。

Nano Mg-Al LDHs were prepared using a hydrothermal method in one step. Effects of synthetic parameters （precursors, temperature, time and alkalinity） on phase purity and crystallite sizes of Mg-Al LDHs were systematically investigated. Reaction products were characterized by powder XRD, SEM and FT-IR. Higher temperature, prolonged reaction time and suitable alkalinity are effective methods for controlling crystallite sizes of Mg-Al LDHs. The competitive hydrolysis ability of precursors are the main factors affecting phase combinations and crystallinity of the reaction products.