Understanding the molecular origin of surface phenomena in water/metal interface based on molecular dynamics approach

The interaction of water with solid substrates plays an important role in various natural phenomena such as catalysis, electrochemistry, and motion of water while having important applications in production of hydrogen, fuel cells, and biological sensors, etc. Understanding the interaction of water and solid surfaces can help in comprehension and control of reactivity of water and surfaces. In the last two decades, water adsorption on metallic surfaces has been studied as a result of great progress in laboratory techniques which along with quantum computations and molecular dynamics simulations, can improve our understanding of water/substrate interfaces and reveal valuable information regarding these interfaces. Stability and structure of adsorbed water on the metallic surfaces are affected by two important aspects of water/metal interfaces; (i) water-surface interaction at the interfacial layer of water/metal and, (ii) the nature and strength of hydrogen bonds in the water which can be affected by the substrate. Molecular dynamics simulation is a helpful tool in studying both aspects. In this study, several systems like water-gold, water-titanium dioxide and water-molybdenum disulfide systems were chosen and, the interactions of water-substrate along with dynamic structure of water were analyzed using molecular dynamics simulations. Furthermore, the relation between structural and dynamical behavior of water and surface properties were studied. The obtained results showed that the positioning, adsorption, and movement of water on a substrates is dependent upon the chemical nature and arrangement of the atoms of the surface. Therefore, the behavior of water molecules on a substrate is a reflection of properties of the surface.