A many-body dissipative particle dynamics study of nanoneedle-liquid interface

Abstract

The wetting of solid surfaces plays an important role in the operation of many natural and engineering systems, for instance, Trolling mode Atomic Force Microscopy whose imaging is definitely affected by a wetting phenomenon. The purpose of this paper is to present a better understanding of the meniscus formation on the outer surface of a nanoneedle. To investigate the wetting process at the micro- and nanoscales, where the experimental observations do not provide rigorous realization, theoretical approaches with their capability to model and predict the system behavior with atomic details can be utilized. To study the time-evolution of the nanomeniscus formation in the solid-liquid interface, an appropriate coarse graining method, called many-body dissipative particle dynamics, is employed. We investigated the correlation between the nanoneedle diameter and nanomeniscus characteristics such as contact angle, meniscus height, evanescent length, and interaction forces. In addition, the effect of a potential parameter, as a means for adjusting the degree of needle wall's wettability, on the meniscus geometry and interaction forces is evaluated. The results of this research have different applications in various fields, such as Trolling-mode AFM and rheological measurements.