摘要：为探究表面效应对动态光散射法测量纳米粒度的影响, 设计一种宽度可调的样品池, 采用基于高速线阵CCD的动态光散射测量系统, 对不同粒径的标准SiO₂颗粒进行测量。结果表明:样品池宽度小于1.3 mm时, 粒径测量值随通道宽度减小线性增大, 宽度为0.6 mm时, 粒径测量值与自由空间中的测量值差距超过5%;样品池宽度较小时, 颗粒布朗运动受到明显影响, 动态光散射仪中使用微量样品池时, 应根据样品池宽度对测量结果进行修正。

关键词：动态光散射；纳米粒度测量；微量样品池；表面效应

Abstract：In order to determine whether the surface effect affect the measurement result of dynamic light scattering or not, a width adjustable sample cell was designed, and measurements of standard particles based on a dynamic light scattering system with high-speed linear CCD was performed. The results show that when the sample cell width is less than 1.3 mm, the measured particle size increase linearly with the decrease of the width. As the width reduces to 0.6 mm, the difference between the measured values and that in the free space can be more than 5%. This demonstrates that the sample cell width affects Brownian motion of particles obviously. Hence, the measured results of dynamic light scattering using micor-cell should be corrected accordingly.

Keywords: dynamic light scattering；nanoparticle size measurement；micro-cell；surface effect