Analytical Techniques for the Wettability and Contact Angle

Abstract

The development of 2D materials as functional surfaces aimed at various developing and technological applications such as sensor, electronics, mechanics, etc. Hence the fundamental understanding of 2D material–liquid interactions becomes very important. The miniaturization and 2D material's sensitivity towards environment creates surface forces that facilitate fluid interactions. In this chapter, the wettability, contact angle measurements, electric double layer (EDL) structures, and the frictional interactions which originates from interactions of 2D material and the liquid is described. The various analytical methods are explained which are used to characterize the 2D materials wetting behavior. The tuning of 2D material's wetting properties is regulated by their substrates and contaminants, various forces like van der Waals forces and surface tension, etc. Additionally, the inherent EDL at the interfaces of 2D material–liquid can be modulated easily. This EDL modulation partly describes the variation in wetting behavior and offers distinct applications like sensors and energy storage applications such as supercapacitors, energy harvesters. Overall, solid–liquid interactions of 2-D materials are fascinating phenomenon enabling the desirable modifications of surface properties, mechanical as well as electrical interactions, and surface behavior.