不同形状的金纳米粒子的表面增强拉曼光谱

使用514 5nm激光激发,第一次得到了不同形状金纳米粒子的表面增强拉曼光谱(SERS)。一般情况下,较短波长(<600nm)激发所获得的增强要小于使用较长波长(>600nm)的激发。然而,对特殊形状的自组装金纳米粒子,由于避雷针效应,即使使用绿光激发也可获得很高增强的SERS。

Surface-enhanced Raman Spectroscopic Study of Gold Nanoparticles with Different Shapes

In this communication, we obtained for the first time the SERS spectra of gold at the laser excitation of 514.5 nm by fabricating the ordered array of gold nanoparticles with special shapes, e.g., sphere, tadpole, and pearlchain. Selfassemble method of these gold nanoparticles is briefly introduced. In general, the enhancement of gold by the laser excitation of short wavelength (600 nm) becuase that the coupling between conduction electrons and interband electronic transitions by using 514.5 nm depresses the quality of the surface plasmon resonance of gold metals considerably. Our observation reveals that the SERS of selfassembly gold nanoparticles with special shape can be rather high even using the green light excitation, which is mainly due to the lightningrod effect.