采用自发成核方法,以NaCl-Na2CO3为助熔剂,生长了毫米级的NaCo2O4晶体。通过X射线衍射对晶体作了表征。利用扫描电子显微镜和原子力显微镜研究了晶体的形貌和生长机理。结果表明:所得晶体是NaCo2O4,属于六方晶系,晶胞参数:a=b=0.2842 nm,c=1.0894 nm,V=0.0761997 nm3。NaCo2O4晶体是沿c轴层状生长的,同时从阴离子配位多面体的角度分析了晶体的形貌。
Millimetre-sized NaCo2O4 crystals were grown from a molten flux based on NaCl-Na2CO3 by spontaneous nucleation method.Details of the preparation and growth procedures are provided.The as-grown crystals were characterized by X-ray powder diffraction(XRPD).The morphology and growth mechanism were investigated by scanning electron microscopy(SEM) and atomic force microscopy(AFM).The results show that the obtained crystal are well crystallized and indexed in a hexagonal crystal system with lattice parameters a=b=0.2842 nm,c=1.0894 nm,and V=0.0761997 nm3.The growth of NaCo2O4 single crystals was controlled by a two-dimensional(2D) layer-by-layer mechanism acting along the c-axis.Furthermore,the morphology of the crystals was also interpreted in the viewpoint of anionic coordination polyhedron growth units.