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报道了一种简单的由单质镁两步制备大量氧化镁单晶纳米片的合成方法．实验中先由镁粉在不加任何助剂的条件下,于180℃水热反应36h制备了反应前驱物Mg(OH)2,再由新制备的氢氧化镁在400℃下焙烧4h获得该氧化镁单晶纳米片．粉末衍射分析表明所制备氧化镁纳米晶为立方结构．扫描电镜分析显示这些纳米晶为片状形貌,其平均厚度约为80nm,宽度为2-6μm．高分辨透射电镜照片显示,氧化镁纳米片中有大量孔状形貌存在,同时电了衍射花样显示,该氧化镁纳米片具有单晶特性．室温荧光光谱显示纳米片在416nm附近有一个强而宽的蓝色荧光峰,在559nm附近有一个相对较弱而宽的绿色荧光峰．BET测试表明该纳米片有较大的表面积(127.21m2/g)．产物表征和实验过程分析显示,片状纳米晶的形成是由前驱物形貌的模板作用所致,而其孔状形貌是由前驱物失水所形成．
Reported a simple method for the preparation of a large number of MgO single crystal nanosheets prepared from two-step Mg. In the experiment, the reaction precursor Mg (OH) 2 was prepared by hydrothermal reaction at 180 ℃ for 36h with magnesium powder without adding any additives, and then the freshly prepared magnesium hydroxide was calcined at 400 ℃ for 4h Magnesium oxide single crystal nanosheet. Powder diffraction analysis shows that the prepared magnesium oxide nanocrystals are cubic structures. Scanning electron microscopy analysis showed that these nanocrystalline flake morphology, the average thickness of about 80nm, a width of 2-6μm. High-resolution transmission electron micrographs showed that a large number of porous morphologies existed in the magnesia nanosheets, and the diffraction patterns of the nanosheets showed that the magnesia nanosheets had single crystal characteristics. Fluorescence spectra at room temperature show that the nanosheets have a strong and broad blue fluorescence near 416 nm and a relatively weak and wide green fluorescence near 559 nm. The BET test showed that the nanosheet has a large surface area (127.21 m2 / g). The characterization of the product and the analysis of the experimental process show that the formation of flaky nanocrystals is caused by the template effect of the precursor morphology, while the pore morphology is formed by the loss of precursors.