Au纳米球壳的光热特性分析与优化

Analysis and Optimization of Au Nanoshell Photothermal Properties

为了寻找单个Au纳米球壳在连续激光激发下的最大表面温度变化及对应的颗粒最优尺寸,利用Mie理论、介电函数尺寸修正模型和热方程定量研究了波长、内核半径和外壳厚度对单个Au纳米球壳光热特性的影响。首先,通过改变Au纳米球壳的内核半径及外壳厚度调节共振峰的大小和位置,并得到所需的颗粒表面温度变化情况。然后,针对颗粒光热特性的应用,给出近红外波段内四个典型波长(800,808,820,1064 nm)下单位入射光强度的最大颗粒表面温度变化量γ_(max)及对应的颗粒最优尺寸。最后,给出了上述波长下单位入射光强度的颗粒表面温度变化量大于0.9γ_(max)的颗粒尺寸分布。该研究对光热治疗、等离子体辅助光催化以及颗粒制备等方面的研究具有重要意义。

We quantitatively investigated the effect of wavelength,core radius,and shell thickness on the photothermal properties of a single Au nanoshell using Mie theory,a size-dependent dielectric function,and heat equation to determine the maximum surface temperature change and optimal particle size under continuous laser excitation.First,the intensity and position of the resonance peak can be adjusted by changing the core radius and shell thickness of the Au nanoshell.The required particle surface temperature variation also can be obtained.Then,the maximum particle surface temperature change per unit incident light intensity γ_(max)at four typical wavelengths(800,808,820,and 1064 nm) in the near-infrared region and the corresponding optimal particle size is obtained to analyze the application of the photothermal properties of the particles.Finally,the particle size distribution with a particle surface temperature change per unit incident light intensity greater than 0.9γ_(max)at the above wavelength is given.This research is essential for photothermal therapy,plasmonic-assisted photocatalysis,and particle synthesis.