纳米ATO颗粒粒度分布的脉冲超声波测量研究

Measurement of Particle Size Distribution of Nano-Antimony Tin Oxide with Pulsed Ultrasonic Wave

讨论了脉冲超声波测量纳米ATO颗粒粒度分布方法中的3个步骤,即超声波衰减谱测量、严格数学模型的选型以及颗粒粒度分布的反演计算。通过发射脉冲超声波并利用变声程方法测量25℃时2%(体积分数)的纳米ATO-H2O分散液的超声衰减谱;选取McClements理论模型叠加BLBL理论模型共同描述纳米ATO颗粒分散液中的超声衰减现象;采用最优正则优化反演算法反演得到纳米ATO颗粒的粒度分布以及平均粒径。脉冲超声法检测结果显示,纳米ATO颗粒的平均粒径为25.6nm,粒度分布为11.4～47.1nm,CPS离心沉降纳米粒度分析仪测定结果分别为22.1nm和10.1～62.6nm。脉冲超声法检测结果与透射电镜图像以及离心沉降纳米粒度分析仪检测结果吻合较好,证明了脉冲超声波测量纳米颗粒粒度分布以及平均粒径的可行性与可靠性。

Three important steps, viz. measuring ultrasonic wave attenuation spectrum, selecting strictly theoretical model and using inversion algorithm for measurement of particle size distribution of nano-antimony tin oxide（ATO） were discussed in this work. An ultrasonic path length-variation de- vice was used to measure the pulsed ultrasonic attenuation spectrum of 2% nano-ATO dispersions at 25 ℃, and the McClements theoretical model coupled with the BLBL theoretical model were selected to describe simultaneously the ultrasonic attenuation spectrum of nano-ATO particles in dispersion. By using the optimum regularization technique to optimize the inversion algorithm, the nano-ATO par- ticle size and mean particle size were obtained. Results showed that the mean particle size D32 of nano-ATO was 25.6 nm and the particle size distribution was 11.4 -47. 1 nm, which were consistent with those obtained by transmission electron microscope and centrifugal sedimentation particle size an- alyzers. Accordingly, the pulsed ultrasonic wave method is feasible and reliable for measuring parti- cle size and particle size distribution of nanoparticles.