脉冲激光技术制备高性能氧化锌纳米材料及其特性研究

Owing to the numerous nanostructures and the excellent physical and chemical properties, zinc oxide nanostructures have attracted extensive attention both experimentally and theoretically. We will use the theoretical and experimental metheds to study the evaporation and expansion mechanism which produced by pulsed laser ablation(PLA). First, we research the formation of the plasma produced by the pulsed laser ablation. Second, we will investigate the physical mechanism of the ZnO nanoparticle produced by the PLA method. We conclude the experimental conditions of how to efficiently produce the large size and long life plasma. Based on previous fundamental research, we will control the plasma distribution in the target chamber by the extrinsic transverse electric field. The further research into the process of ablating Zn will promote the production of high-performance nanomaterials in different medium. Preparation of high-quality and well controlled nanomaterials through laser ablation is predicated by reliable experiment and theory. The continuous improved pulsed laser ablation technology will make the manufacture of high-quality, high-performance and well controlled nanomaterials possible. And it is the effective scheme of the preparation of nanomaterials, which is difficult to control.

本申请课题拟采用实验和理论相结合的方法，分析单束和双束脉冲激光烧蚀Zn等材料在不同介质中的蒸发和膨胀到生成纳米材料的物理机制。从研究产生的等离子体特性入手，对脉冲激光烧蚀产生纳米材料的主要机理做深入探讨。总结出能够产生电离效率高、大尺寸空间膨胀和寿命长的等离子体实验条件。在此研究基础上，通过外加横向电场调控其内部离子空间的分布，以及对烧蚀过程的研究，最终实现并完善脉冲激光烧蚀Zn等材料在不同介质中制备出高性能的Zn/ZnO等纳米材料。为激光烧蚀制备高质量、可控的纳米材料提供可靠的实验和理论依据。脉冲激光烧蚀技术的不断完善必将使高质量、高性能、更均匀可控的纳米材料的制备得以顺利实现，是解决在纳米材料的制备中出现难以控制的有效途径。

本项目重点研究了高功率纳秒脉冲激光在各种液体中与Zn等金属材料相互作用生成各种形状的纳米材料。在1064nm波长条件下，使用激光在氨水溶液中（V水：V氨水=7:1~5:1）烧蚀Zn靶材制备出ZnO纳米材料和多孔纳米笼。而且在烧蚀过程中可以通过调节氨水和水的比例调控空心结构的比例。在ZnO纳米材料和ZnO多孔纳米笼的形成过程中氨水起到了非常重要的作用。我们还通过激光在水溶液中烧蚀锌靶得到ZnO/Zn(OH)2复合纳米材料，与在氨水溶液中合成的氧化锌纳米笼形成对比来探究从ZnO/Zn(OH)2复合纳米材料到ZnO纳米笼的转变过程。通过液相脉冲激光烧蚀合成表面多孔的空心纳米结构的方法在其他空心多孔材料的合成方面具有重要的研究意义。而且我们合成的这种离子簇的嵌入的空心多孔的ZnO，而不是通常的离子团簇的表面附着，这种结构会使ZnO多孔纳米笼在未来作为特定的紫外线吸收设备。使用脉冲激光液相烧蚀合成技术可控调节制备了超精细的空心多孔TiO2纳米材料以及两种不同构型的ZnS/Zn纳米复合材料，并探索了其可控合成机理和新方法。