Modulating the Water Contact Angle Using Surface Roughness: Interfacial Properties of Hexagonal Boron Nitride...

Area of Science:

• Materials Science
• Computational Chemistry
• Surface Science

Background:

• Hexagonal boron nitride (hBN) shows promise for water-related applications.
• Understanding hBN's interaction with water, particularly on rough surfaces, is crucial but remains unclear.

Purpose of the Study:

• To investigate the influence of surface roughness and force field selection on hexagonal boron nitride (hBN) wettability using molecular dynamics (MD) simulations.
• To analyze the contributions of different interaction types to adhesion and optimize simulations for desalination technologies.

Main Methods:

• Utilized quantum mechanical calculations for accurate hBN surface charge distribution.
• Performed molecular dynamics (MD) simulations with free energy calculations for hBN-H2O interfaces.
• Incorporated surface roughness into the simulation models and compared results with experimental data.

Main Results:

• Simulations with surface roughness and FF-3 force fields closely matched the experimental water contact angle (WCA) of 66° for hBN.
• FF-2 force fields yielded an unrealistic WCA of 0°, emphasizing the critical role of force field selection.
• Dissected the impact of roughness on WCA, detailing contributions from electrostatic and Lennard-Jones interactions to the work of adhesion.

Conclusions:

• Realistic surface representation and appropriate force field selection are essential for accurate simulation of hBN wettability.
• The findings provide insights into interfacial properties, paving the way for improved desalination and water technologies.