采用离子束溅射技术和热氧化工艺,对预先制备的ZnO纳米线表面进行纳米CuO修饰,研究了不同溅射工艺条件下对形成的CuO/ZnO纳米线异质结构的影响,通过控制溅射参数成功地合成出不同CuO量子点尺寸和分布密度的CuO/ZnO量子点异质结和CuO为壳层的CuO/ZnO同轴纳米线异质结构.将X射线衍射仪(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)用于研究样品的结构和形貌.实验结果表明,溅射在ZnO纳米线表面的Cu膜的厚度对形成的CuO/ZnO异质结构起着重要的作用.在Cu膜适度较薄时,获得了直径仅5 nm、分布较均匀的高密度(2.05×1010mm-2)CuO/ZnO量子点异质结;而Cu膜较厚时,形成的是CuO/ZnO同轴纳米线异质结构.利用高分辨透射电子显微镜(HRTEM)进一步对量子点异质结和同轴纳米线异质结的界面晶体结构进行了研究.
CuO/ZnO quantum dot heterojunctions with different sizes and distribution density and CuO/ZnO coaxial nanowire heterostructures have successfully been synthesized by controlling the process parameters of ion beam sputtering and thermal oxidation technology.X-ray diffraction(XRD)and transmission electron microscopy(TEM) were used to study the structures and morphologies of CuO/ZnO samples.The results indicate that the thickness of sputtering Cu thin films plays an important role in the formation of CuO/ZnO heterostructure.The CuO quantum dots with a diameter of only 5 nm and high density of 2.05×1010 mm-2 have been obtained for a shorter sputtering time of 1 min.However,the CuO/ZnO coaxial nanowire heterostructure formed for a longer sputtering time of 10 min.The crystal structures at the interfaces of the quantum dot heterostructures and the coaxial nanowire heterostructures were also investigated using high resolution transmission electron microscopy.