Understanding surface wettability: insights from experiments, molecular simulations, and first-principles theory

Area of Science:

• Surface science and interfacial phenomena.
• Materials science and engineering.
• Computational chemistry and physics.

Background:

• Wettability is crucial for diverse applications but research is fragmented across experimental and computational methods.
• Inconsistencies in protocols and models hinder a unified understanding of surface-liquid interactions.
• Classical wetting models fail at the nanoscale, necessitating advanced characterization.

Purpose of the Study:

• To critically synthesize advances in wettability research across experimental, atomistic simulation, and first-principles modeling.
• To identify agreements, controversies, and knowledge gaps in wettability studies.
• To provide a roadmap for consistent, reproducible, and predictive wettability research.

Main Methods:

• Review and critical synthesis of existing literature on wettability.
• Analysis of experimental characterization techniques.
• Evaluation of molecular dynamics simulations and quantum mechanical calculations.

Main Results:

• Classical wetting models break down at nanometric scales.
• Contact angle is not a unique descriptor; complementary quantities are essential.
• Interfacial modeling choices significantly impact predicted wettability, leading to inconsistencies.

Conclusions:

• A unified framework is needed to link wettability observations across length and time scales.
• Complementary thermodynamic, structural, and dynamic data are vital for characterizing solid-liquid affinity.
• Integrating interfacial chemistry, molecular structure, and macroscopic observables will improve wettability predictions.