Eklöf Johnas, Gschneidtner Tina, Lara-Avila Samuel, Nygård Kim, Moth-Poulsen Kasper
Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg SE-412 96, Sweden. Email:
Department of Microtechnology and Nanoscience, Chalmers University of Technology, Gothenburg SE-412 96, Sweden.
RSC Adv. 2016 Nov 13;6(106):104246-104253. doi: 10.1039/c6ra22412a. Epub 2016 Oct 25.
The self-assembly of nanoparticles on substrates is relevant for a variety of applications such as plasmonics, sensing devices and nanometer-sized electronics. We investigate the deposition of 60 nm spherical Au nanoparticles onto silicon dioxide (SiO) substrates by changing the chemical treatment of the substrate and by that altering the surface charge. The deposition is characterized by scanning electron microscopy (SEM). Kelvin probe force microscopy (KPFM) was used to characterize the surface workfunction. The underlying physics involved in the deposition of nanoparticles was described by a model based on Derjaguin-Landau-Verwey-Overbeek (DLVO) theory combined with random sequential adsorption (RSA). The spatial statistical method Ripley's -function was used to verify the DLVO-RSA model (ERSA). The statistical results also showed that the adhered particles exhibit a short-range order at distances below ~300 nm. This method can be used in future research to predict the deposition densities of charged nanoparticles onto charged surfaces.
纳米颗粒在基底上的自组装与多种应用相关，如等离子体学、传感设备和纳米级电子学。我们通过改变基底的化学处理方式并由此改变表面电荷，研究了60纳米球形金纳米颗粒在二氧化硅（SiO）基底上的沉积情况。沉积情况通过扫描电子显微镜（SEM）进行表征。开尔文探针力显微镜（KPFM）用于表征表面功函数。基于德亚金-朗道-韦弗伊-奥弗贝克（DLVO）理论并结合随机顺序吸附（RSA）的模型描述了纳米颗粒沉积过程中涉及的基础物理原理。空间统计方法里普利函数用于验证DLVO-RSA模型（ERSA）。统计结果还表明，在距离低于约300纳米时，附着的颗粒呈现出短程有序排列。该方法可用于未来研究中预测带电纳米颗粒在带电表面上的沉积密度。
