A comparative study of the wetting behaviors on a rutile TiO2 having different surface morphologies

Abstract

Interfacial characteristics and wetting behaviors of titanium dioxide surface along with its various morphologies has recently been studied as an important subject. In this paper the water wetting behaviors and adsorption action of a water droplet on a rutile TiO2 with various surfaces and morphologies has been investigated through classical molecular dynamics simulation approaches. Also, interface water on a rutile TiO2 with various surfaces is analyzed based on the distribution and formation of water molecules in the first and second layer. A rutile TiO2 (011), (101), (110) and (111) has been chosen, which are procured by exerting crystallographic data. The simulation results illustrated that the strong interaction between water molecules and surface depends on the higher density of water molecules in the interface layer due to the van der Waals interaction. Also, molecules of water with their hydrogen atoms pointed towards the oxygen atoms of the titanium dioxide and titanium locations of titanium dioxide where fewer molecules of water could be found. Furthermore, that there is no significant difference on pinning the water droplet on the TiO2 surface concerning different surfaces. Further investigations revealed that the TiO2 (110) surface has the lowest value of contact angle and as a result has the highest hydrophilic surface among the investigated structure of TiO2. Also, the average interaction energy disclosed the difference between the maximum and minimum energy in the TiO2 (110) surface is very high that resulting to create a large energy barrier, which inhibits the movement of molecules of water at the water/TiO2 (110) interface. These results are extracted from calculation of the distribution of the electrical charge, center of mass, contact angle, interaction energy, mean squared displacement, density profiles. All results are in line with the reported quantum calculations and experimental data.