摘要
以白云石为原料通过二次酸浸、EDTA-氨水络合法制得纳米MgO晶体,并采用XRD、FT-IR、SEM、TEM等手段对其进行了表征.研究表明,EDTA/PEG分子具有结构导向作用,使Mg(OH)2分子呈外延辐射状均匀生长.550-650℃煅烧前驱体制得的MgO纳米微片生长均匀,为立方晶系结构的单晶,具有类似花瓣状的菱面微片结构,其厚度约为10-20nm,最大面积可达1μm2左右.氧化镁晶体沿[100]方向取向生长,并保留了前驱体的外延辐射状生长特性.结合热力学及动力学等相关理论研究了氧化镁纳米微片的取向生长机理.
Rhombic magnesia flakes with multi interspaces were prepared by calcining magnesium hydrate. The precursor of MgO could be obtained via acid immersing twice and ammonia depositing from dolomites. The structure, morphology, and composition of MgO and its precursor were characterized by means of XRD, FT-IR, SEM, and TEM methods. The results indicated that EDTA and PEG molecules were possessed of the effect directing the radial epitaxial growth of Mg(OH)2 flakes. The rhombic magnesia nanoflakes with 10-20 nm in thickness and up to 1 μm^2 in area of main surface are single crystal with cubic crystal structure. It grows with a preferred orientation along the [100] direction and inherits the features of radial epitaxial growth of Mg(OH)2. The orientated growth mechanism of the MgO nanoflakes was studied based on corresponding thermodynamics and dynamics theories.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2007年第3期433-437,共5页
Acta Physico-Chimica Sinica
基金
湖南省科技重点攻关项目(03ssy1008)
中南大学研究生创新基金(2005010073)资助
关键词
菱面片层MgO
热分解
微观形貌
晶体生长
影响因素
Rhombic magnesia flakes
Thermal decomposition
Microscopic morphology
Crystal growth
Effect factors