基于三维时域有限差分法,计算了非球对称单芯帽纳米颗粒在不同结构参数作用下的局域表面等离子体共振(LSPR)响应。采用模板法和真空蒸镀技术制备了SiO₂@Au芯帽结构纳米颗粒,通过透射电子显微镜和紫外可见近红外分光光度计对其形貌和光学性质进行了测量分析,获得了金壳厚度、芯壳比、芯径和金属表面覆盖率等纳米结构参数对LSPR峰值吸收波长和吸收截面的影响规律。结果表明,芯帽纳米颗粒结构参数的微小改变会导致LSPR峰在可见光到近红外波段的宽带红移。

The localized surface plasmon resonance (LSPR) response of single core-capped non-spherically-symmetric nanoparticles with different structural parameters is calculated based on the three-dimensional finite-difference time-domain method. The SiO2@Au core-capped nanoparticles are prepared by the template method and the vacuum evaporation technique. The surface morphologies and optical properties are measured and analyzed by the transmission electron microscopy and the UV-visible near-infrared spectrophotometer. The effects of structural parameters such as metal shell thickness, core-shell ratio, core diameter and metal surface coverage on the LSPR peak absorption wavelength and absorption cross section are obtained. The results indicate that a small change of the structural parameters of core-capped nanoparticles results in a broadband red shift of the LSPR peak in the visible to near infrared spectral range.