固基银膜材料的制备—形貌控制及性质分析

【作者】 易早；

【导师】 牛冬梅； 易有根；

【作者基本信息】 中南大学 ， 凝聚态物理， 2010， 硕士

【摘要】 贵金属纳米结构的表面等离子体共振(SPR)吸收性质使其在传感、太阳能吸收、医学热疗、局域场增强、激光惯性约束聚变等领域具有重要的应用价值。在传感探测、化学催化、太阳能吸收等领域应用金属纳米结构时,液相纳米粒子溶胶由于粒子数密度不固定、粒子不稳定、难以回收和重复使用,因此不方便直接应用,当前研究的热点是使纳米结构在固相基底上形成阵列或薄膜,探测基底上纳米结构的性质。另外,在惯性约束聚变研究中,需要在基底上构筑金属纳米结构,调节其吸收波长与激光波长相对应,研究基底在强激光作用下的响应。因此,有必要发展出在固相基底上生长金属纳米结构的简便方法。本论文研究了固基贵金属膜材料的制备、形貌控制及其在光学性能方面的应用研究。应用扫描电子显微镜、原子力显微镜、紫外可见分光光度计、荧光光谱仪、X射线衍射仪、拉曼光谱等技术来研究所制膜材料的性质和分析金属的沉积机理,实现了由“材料制备”、“材料组成形貌分析”到“材料应用”的交叉、系统性研究。论文的主要内容如下：1.用硅烷化处理的玻璃基底吸附三角形银纳米盘种子,以单宁酸为还原剂,在基底上原位生长三角形银纳米粒子聚集结构；用硅烷化处理的玻璃基底吸附类球形金纳米种子,以荧光灯为光源,在基底上原位生长银纳米粒子聚集结构。基底的吸收光谱上呈现出明显的电偶极子耦合吸收峰,研究了该峰随反应时间的变化。探讨了不同种子和反应条件对基底上粒子形貌和吸收光谱的影响。2.采用化学镀的方法,通过控制AgNO3和络合剂的摩尔比以及反应温度,在玻璃基底上原位生长不同结构的银纳米粒子。研究了基底的SPR吸收峰,考察了银纳米粒子的形貌对其薄膜基底SERS活性的影响。3.采用铜箔为活性基底,研究了在相同的实验条件下,通过加入不同种类的络合剂,得到形貌各异的银纳米粒子薄膜。采用带有银树枝结构的铜箔为活性基底,在相同的实验条件下,通过加入分散剂PVP,采用多步法置换金盐,得到Au/Ag双金属树枝结构,研究了不同置换次数下Au/Ag双金属树枝结构的拉曼增强效应。更多还原

【Abstract】 Noble metal nanostructures take on surface plasmon resonance (SPR) absorption under irradiation of incident light, thus show various potential applications in the fields of sensing, solar energy absorption, biomedical thermotherapy, local filed enhancement, laser induced inertial confinement fusion and so on. In the fields of sensing, chemical catalysis, solar energy absorption, the number nano-particles are not fixed in liquid. The nano-particles are difficult recovery and reuse, so inconvenient for direct application. The research focuses are to make nano-structure form array column or thin film on the solid phase substrates and to detect the character of nano-structured on substrate. In laser induced inertial confinement fusion, in addition, metal nano-structures need be built on the substrates; the absorption wavelength and the laser wavelength are transferred corresponding; the response of substrate is studied in the harder laser. Therefore, it is necessary to develop an easy way make metal nano-structures grow on solid phase substrates.This thesis deseribes the preparation of noble metal films on solid substrates, morphologieal control and the studies of their properties such as optical, electrical and eatalytic properties. The properties of the films and metal deposition mechanism were investigated by using scanning electron microscopy (SEM), atomic force microsceopy (AFM), UV-Vis spectrophotometer, fluorescence spectroscopy, X-ray diffraction measurement (XRD), Raman spectroscopic analysis, ete. Some important results obtained are deseribed as follows:1. Triangular silver nanoplates on the surface of glass substrate have been synthesized by small triangular silver nanoplate seeds with the assistance of Tannin. Silver nanoparticles aggregates adsorbed on glass substrates were in-situ prepared under irradiation of a fluorescent lamp after the substrates were silanized and attached with metal seeds. A new strong band appeared in the absorption spectra of the substrates due to the interparticle dipole-dipole coupling of SPR response of the silver particles. The change of this band with irradiating time and the influence of different seeds and reacting conditions on the morphology and absorption properties of the silver structrures on the substrates were studied.2. The novel silver nanoparticles were successfully synthesized by a novel electroless plating approach on glass substrate. The formation of silver nanoparticles was attributed to the molar ratio of AgNO3 and complexing agent and the influence of reaction temperature. The SERS activity of the substrate degree on the effect of surface morphology of silver nanoparticles.3. The different morphology of thin films of silver nanoparticles has been synthesized by using the copper active substrate with different types of complexing agents at the same experimental conditions. Ag/Au Bimetallic Nanostructures have been synthesized by using the Ag dendrites on the Cu substrate as active substrate with multi-stage replacement at the same experimental conditions. The SERS activity of the Ag/Au Bimetallic Nanostructures was studied.更多还原