  This article covers thermodynamic, dynamic, and kinetic models that are
suitable for the analysis of wetting, adsorption, and related interfacial
phenomena in colloidal and multiphase systems. Particular emphasis is made on
describing crucial physical assumptions and the validity range of the described
theoretical approaches and predictive models. The classical sharp interface
treatment of thermodynamic systems where a perfectly smooth surface is assumed
to separate homogeneous phases can present significant limitations when
analyzing systems that are subject to thermal motion and present multiple
metastable states caused by interfacial heterogeneities of nanoscale
dimensions. Mesoscopic approaches such as stochastic Langevin dynamics can
extend the application of sharp interface models to a wide variety of systems
exhibiting metastability as they undergo thermal motion. For such metastable
systems, dynamic and kinetic equations can describe the evolution of observable
(macroscopic) variables as the system approaches thermodynamic equilibrium.
Sufficiently close to equilibrium, Kramers theory of thermally activated escape
from metastable states can be effectively employed to describe diverse wetting
and interfacial processes via kinetic equations. Future directions for further
advancement and application of thermodynamic, dynamic, and kinetic models are
briefly discussed in the context of current technological developments
involving nanoparticles, nanofluidics, and nanostructured surfaces.
