熔盐法制备片状及多孔棒状形貌氧化镁

Synthesis of Flaky and Porous Rod-like MgO Powders by Molten Salt Method

以MgCl2、CaCO3和NaCl、KCl为原料,采用熔盐法制备了片状和多孔棒状形貌MgO粉体。借助XRD、FT-IR、SEM等手段对产物进行了分析和表征。结果表明:原料在700℃热处理后,经PEG溶液浸泡得到的氢氧化镁前驱物形貌为纤维状,经EDTA-PEG溶液浸泡得到的氢氧化镁前驱物形貌为片状。纤维状氢氧化镁分解为氧化镁产物后呈多孔棒状形貌,直径介于20～80 nm,长径比介于40～100;片状氢氧化镁分解为氧化镁产物后仍保持片状形貌,厚度介于30～50 nm,直径介于200～500 nm,单片表面积最大可达1.0μm2。

Haky and porous rod-like MgO powders were prepared through molten salt synthesis with MgCl2, CaCO3, NaCl,KCl as raw materials. The products were studied by using TEM, FT-IR and XRD and results indicated that Mg （OH）2 fibers were formed in PEG solution while Mg （OH）2 flakes in PEG-EDTA solution after the raw materials were calcined at 700 ℃. The product MgO obtained by decomposition of the fiber-like Mg（OH） 2 was porous rod-like, with 20 - 80 nm in diameter and 40- 100 in length-to-width ratio. The product MgO obtained from the decomposition of flake-like Mg（ OH）2 kept the flake shapes with 30 -50 nm in thickness, 200 -500 nm in diameter and 1.0 μm^2 in maximum surface area.