Kinetic Monte Carlo simulation of nanoparticle film formation via nanocolloid drying
Kinetic Monte Carlo simulation of nanoparticle film formation via nanocolloid drying
复制标题
通过纳米胶体干燥形成纳米粒子膜的动力学蒙特卡罗模拟
DOI：
10.1007/s11051-017-3898-3
复制
发表时间：
2017
影响因子：
2.5
通讯作者：
Yuki Kameya
中科院分区：
文献类型：
--
作者：
Yuki Kameya;Kenjiro Torii;Shuichiro Hirai;Massoud Kaviany;Yuki Kameya
对纳米胶体干燥过程中纳米颗粒成膜过程进行了动力学蒙特卡罗模拟。提出的二维模型描述了纳米粒子在干燥纳米胶体薄膜垂直平面内的动力学。用含时化学势控制了溶剂挥发引起的气液界面运动，计算了包括布朗扩散和聚集体生长在内的颗粒动力学。模拟是在不同的Peclet数下进行的，Peclet数基于溶剂挥发和纳米粒子扩散的速率比。在较高的Peclet数下，纳米颗粒聚集在液膜的顶层，最终形成一层皮肤，导致形成具有致密堆积结构的颗粒膜。在较低的Peclet数下，增强的颗粒扩散导致颗粒在块体胶体中显著聚集，由此形成的薄膜结构变得高度多孔。模拟结果显示了实验报道的干燥纳米胶体的一些典型特征。最后，讨论了模型的潜力以及仍然存在的挑战。
A kinetic Monte Carlo simulation of nanoparticle film formation via nanocolloid drying is presented. The proposed two-dimensional model addresses the dynamics of nanoparticles in the vertical plane of a drying nanocolloid film. The gas–liquid interface movement due to solvent evaporation was controlled by a time-dependent chemical potential, and the resultant particle dynamics including Brownian diffusion and aggregate growth were calculated. Simulations were performed at various Peclet numbers defined based on the rate ratio of solvent evaporation and nanoparticle diffusion. At high Peclet numbers, nanoparticles accumulated at the top layer of the liquid film and eventually formed a skin layer, causing the formation of a particulate film with a densely packed structure. At low Peclet numbers, enhanced particle diffusion led to significant particle aggregation in the bulk colloid, and the resulting film structure became highly porous. The simulated results showed some typical characteristics of a drying nanocolloid that had been reported experimentally. Finally, the potential of the model as well as the remaining challenges are discussed.