Born Philip, Schön Volker, Blum Susanne, Gerstner Dominik, Huber Patrick, Kraus Tobias
INM-Leibniz Institute for New Materials , Campus D2 2, 66123 Saarbrücken, Germany.
Langmuir. 2014 Nov 11;30(44):13176-81. doi: 10.1021/la503551d. Epub 2014 Oct 27.
Alkylthiol-coated gold nanoparticles spontaneously segregate from dispersion in toluene to the toluene-vapor interface. We show that surface tension drops during segregation with a rate that depends on particle concentration. Mono- and multilayers of particles form depending on particle concentration, time, and temperature. X-ray reflectometry indicates fast monolayer formation and slow multilayer formation. A model that combines diffusion-limited segregation driven by surface energy and heterogeneous agglomeration driven by dispersive van der Waals particle interactions is proposed to describe film formation.
烷基硫醇包覆的金纳米粒子会自发地从甲苯分散液中分离至甲苯-蒸汽界面。我们发现，分离过程中表面张力下降，其速率取决于粒子浓度。根据粒子浓度、时间和温度的不同，会形成单层和多层粒子。X射线反射测量表明单层形成迅速，多层形成缓慢。本文提出了一个模型，该模型结合了由表面能驱动的扩散限制分离和由分散性范德华粒子相互作用驱动的非均相团聚，用于描述薄膜形成过程。
