Morphological phase transitions of thin fluid films on chemically structured substrates

TL;DR

This paper investigates how thin liquid films on chemically patterned substrates undergo morphological phase transitions, revealing conditions for both first-order and continuous changes in interfacial configurations.

Contribution

It introduces a microscopic density functional theory-based model to analyze phase transitions of thin films on chemically structured surfaces, providing detailed phase diagrams.

Findings

Identification of first-order and continuous phase transitions

Determination of phase diagrams for different effective potentials

Conditions for morphological changes in thin films

Abstract

Using an interface displacement model derived from a microscopic density functional theory we investigate thin liquidlike wetting layers adsorbed on flat substrates with an embedded chemical heterogeneity forming a stripe. For a wide range of effective interface potentials we find first-order phase transitions as well as continuous changes between lateral interfacial configurations bound to and repelled from the stripe area. We determine phase diagrams and discuss the conditions under which these morphological changes arise.