Molecular Dynamics Simulation Insight into Water Condensation as a Function of Surface Hydropobicity

Water condensation plays a major role in a wide range of industrial applications. Over the past few years, many studies have shown interest in designing surfaces with enhanced water condensation and removal properties. To advance these designs a molecular scale understanding of the water behavior as a function of surface hydrophobicity is strongly needed. Using molecular dynamics computer simulations of well-characterized alkanethiol self- assembled monolayers with different head group chemistries, here we quantify the role of surface hydrophobicity on water condensation. We measured the water condensation rates on different surfaces and linked that behavior to well established surface characteristics to give a more complete picture of the role of surface hydrophobicity on the behavior of water. We observed a remarkable correlation between our results and the role of surface hydrophobicity on the water compressibility, interfacial thermal conductance and contact angle when we compare data across different studies. Examining the total interaction energy between water and the surface, density fluctuations near the surface, the formation, growth mechanism and stability of water clusters, and the wetting process on the surface we are able to provide insight into the water condensation process on different surfaces as a function of surface hydrophobicity.