【作者】 刘钟馨；

【导师】 宋宏伟；

【作者基本信息】 中国科学院研究生院（长春光学精密机械与物理研究所） ， 凝聚态物理， 2006， 博士

【摘要】 纳米材料是纳米技术应用的基础，低维金属纳米材料是纳米材料基本物理性质研究的理想模型，其特殊的光、电、磁等方面的优越的物理性质使其在生物领域和纳米器件研制方面有重要的应用前景。本文以金／银等贵重金属为研究对象，设计合成了两种新材料体系：金纳米球壳、银纳米链，研究了它们的特殊的光吸收性质和光热转换性质，并利用这些特性，在肿瘤的近红外热疗方面开展了探索性研究；探讨了飞秒激光对这些金属纳米材料形貌和结构的影响；制备了银包覆的稀土氧化物发光材料，研究了金属纳米粒子的包覆对Eu³⁺发光性质的影响。取得的主要成果有： （1） 采用湿化学法制备了Au纳米球壳。Au纳米球壳的粒径约为20 nm，壳层厚度约为5 nm，尺寸分布比较均匀，具有良好的近红外吸收特性。首次研究了这种材料的光热转换性质：经808 nm的激光（5 W／cm²）照射后，在12 min内，温度可升高30℃。 （2） 采用湿化学法利用水／油的相界面反应制备了具有超宽近红外吸收特性的Ag纳米链网状材料。Ag纳米链直径约为50 nm，长度分布范围较宽，吸收强度大，吸收峰宽而且平坦，光热转换性质更加优越。 （3） 在国内，首次将上述具有近红外吸收特性的金属纳米材料应用于生物体外和体内的热疗实验中。实验结果表明，近红外光热疗对于肿瘤细胞和肿瘤组织有一定的抑制作用。 （4） 发现了飞秒激光诱导金属纳米材料形貌改变的现象并分析了机理。Ag纳米棒水溶胶在800 nm的飞秒激光辐照下发生了光化学反应，在电子喷射和表面光化学反应的作用下形成了零维的纳米粒子，并随着辐照时间的增长，粒子尺寸逐渐变小。空心的金纳米球壳，在800 nm飞秒激光辐照形成的静电场作用下形成了不同长度的纳米管。 （5）研究了液相和粉末状态下的Ag包覆的Y₂O₃:Eu³⁺纳米粒子的发光性质。研究发现，Ag纳米粒子能有效的提高Y₂O₃:Eu³⁺的分散性，并在一定程度上阻止了Eu³⁺向溶液中的振动基团的无辐射跃迁，使其在液相中的荧光强度增强。更多还原

【Abstract】 Nanomaterials were the base of the application of nanotechnology. Low-dimensional metal nanostructured materials were the perfect models in the study of the essential physical properties of nanomaterials. They had the significant applications in biomedicine and nanodevices because of their unique electronic, optical, and mechanical properties. In this thesis, noble metal gold and silver were selected as the objects for study. Two kinds of nanomaterials were synthesized: gold nanoshell and silver nanochain. The special absorption and photothermal conversion properties were studied and the thermal therapy experiments were carried out in vitro and vivo. The effect of the femtosecond laser in the shape changes of the metal nanomaterials were discussed. The silver enwrapped rare earth oxide was prepared and the influence of the silver nanoparticles in the luminescence of the Eu³⁺ was researched. The main results are as follows:（1） The gold nanoshells were prepared by a wet-chemical synthesis method. The diameter was 20 nm, the thickness of the shell was 5 nm and the distribution of the size was uniform. This kind of material gained the excellent absorption in near-infrared （NIR） and photothermal conversion properties. The temperature of the hydrosol was increased as high as 30℃ under exposure of an 808 nm coherent diode laser with powder density of 5 W/cm².（2） Cross-sectional Ag nanochains were prepared using the method of water/oil emulsion. The diameter of the Ag nanochains was 30 nm and the distribution of the length was wide. This kind of material demonstrated strong and super-wide absorption更多还原