School of Materials Science and Engineering, Dalian University of Technology , Dalian 116024, China.
ACS Appl Mater Interfaces. 2013 Nov 27;5(22):12066-72. doi: 10.1021/am403876e. Epub 2013 Nov 11.
One-dimensional GaN nanorods with corrugated morphology have been synthesized on graphite substrate without the assistance of any metal catalyst through a feasible thermal evaporation process. The morphologies and microstructures of GaN nanorods were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). The results from HRTEM analysis indicate that the GaN nanorods are well-crystallized and exhibit a preferential orientation along the [0001] direction with Ga(3+)-terminated (101̅1) and N(3-)-terminated (101̅1̅) as side facets, finally leading to the corrugated morphology surface. The stabilization of the electrostatic surface energy of {101̅1} polar surface in a wurtzite-type hexagonal structure plays a key role in the formation of GaN nanorods with corrugated morphology. Room-temperature cathodoluminescence (CL) measurements show a near-band-edge emission (NBE) in the ultraviolet range and a broad deep level emission (DLE) in the visible range. The crystallography and the optical emissions of GaN nanorods are discussed.
一维具有波纹形貌的 GaN 纳米棒在没有任何金属催化剂的帮助下，通过一种可行的热蒸发工艺，在石墨衬底上合成。GaN 纳米棒的形貌和微观结构通过 X 射线粉末衍射（XRD）、扫描电子显微镜（SEM）和高分辨率透射电子显微镜（HRTEM）进行了表征。HRTEM 分析的结果表明，GaN 纳米棒结晶良好，表现出沿[0001]方向的择优取向，Ga(3+)-端（101̅1）和 N(3-)-端（101̅1̅）为侧平面，最终导致表面呈现波纹形貌。在纤锌矿型六方结构中，{101̅1}极性表面的静电表面能稳定化在形成具有波纹形貌的 GaN 纳米棒中起着关键作用。室温下的阴极发光（CL）测量显示在紫外范围内有近带边发射（NBE），在可见范围内有宽的深能级发射（DLE）。讨论了 GaN 纳米棒的晶体学和光学发射。
