两步法实现ZnO纳米结构的集成及光学性质研究

Integration and Optical Properties of ZnO Nanostructures by Two-step Thermal Evaporation Approach

通过简单的两步热蒸发方法成功地实现了ZnO纳米管和纳米棒的集成。SEM结果表明,大量的纳米线以层层生长的机理从约200℃低温Si基片表面生长出来。EDS和XRD结果进一步表明第一步所制备的样品主要是由大量Zn和少量Zn的氧化物组成。第二步所制备样品的SEM和TME图像证实了在高温下以第一步所制备的样品作为第二步的基片,可实现纳米管和纳米棒的集成。TEM图像表明,纳米管的表面所生长的纳米棒是单晶的。通过改变工作气压,可调控纳米管表面纳米棒的尺寸和形貌,实现ZnO纳米结构可控生长。室温光致发光谱表明,样品的光学性质可通过可控的形貌来调制。

Integration of ZnO nanotubes and nanorods is realized through simple two-step thermal evaporation deposition process. SEM image indicates that a number of nanowires grow from -200℃ Si substrate via layer-by-layer growth model. EDS and XRD results display that one-step-prepared samples consist of plentiful Zn and little oxide. SEM and TEM images of samples prepared at step two testify that at high temperature, integration of ZnO nanotubes and nanorods is realized using the one-step-prepared samples as substrate. TEM results indicate that the nanorods on the surface of nanotubes are single crystal. The variety of work pressures may control the size and morphology of nanorods located on the surface of nanotubes, resulting in the formation of ZnO nanostructures with controllable morphologies. The room-temperature photoluminescence spectra show that the optical properties of samples can be modulated by controllable morphology.