论文部分内容阅读
相对于单一金属纳米材料,二金属复合纳米材料具有更大的潜在应用价值.基于时域有限差分方法,研究了SiO_2-Ag-Au和SiO_2-Au-Ag二金属三层纳米管的消光光谱,并对其局域表面等离激元共振(localized suIrfaceplasmon resonance,LSPR)特性进行了分析.研究发现,内核尺寸变大将导致上述两种金属纳米管LSPR峰红移;内层金属及外层金属壳层厚度增大均会导致其LSPR峰蓝移.银壳厚度变化对纳米管LSPR的调制作用大于金壳厚度变化造成的影响.上述现象可以利用等离激元杂化理论及自由电子和振荡电子变化的竞争机制进行分析.
Compared with single metal nanomaterials, binary metal composite nanomaterials have more potential applications. Based on the finite difference time-domain method, the extinction spectra of two-layer nanotubes of SiO_2-Ag-Au and SiO_2-Au-Ag were studied. (LSPR) characteristics of the localized surface plasmon resonance (LSPR) were analyzed.It was found that the bigger the core size would lead to the red shift of the LSPR peaks of the two kinds of metal nanotubes, the inner layer metal and the outer layer metal shell The increase of layer thickness will lead to the blue shift of LSPR peak.The modulation effect of silver shell thickness on the nanotube LSPR is greater than that caused by the change of gold shell thickness.The above phenomenon can be based on the theory of plasmon hybrid and free electrons and oscillatory electrons Change the competitive mechanism for analysis.