Effects of surface wettability on (001)-WO3 and (100)-WSe2 : A spin-polarized DFT-MD study

An extensive understanding of WO3 and WSe2 bulk crystalline structures and explicit solvent effects on (001)-<br> WO3 and (100)-WSe2 facets are essential for design of efficient (photo) electrocatalysts. The atomistic level<br> understanding of both WO3 and WSe2 bulk solids and how water solvation processes occur on WO3 and WSe2<br> facets are nowadays characterized by a noticeable lack of knowledge. <br> Herein, forefront Density Functional Theory-based molecular dynamics have been conducted for assessing<br> the role of an explicit water environment in the characterization of solid surfaces. Water at the interface<br> and H-bonds environment, as well as WO3 and WSe2 surface activity, will be described in terms of surface<br> wettability and interfacial water dynamics, revealing the relevance of treating explicitly liquid water and its<br> dynamics in assessing catalytic features. We provide pieces of evidence of the hydrophobic character shown by<br> (001)-WO3 and (100)-WSe2 facets. A preferential in-plane hydration structure of the first water layer has been<br> detected at both (001)-WO3 and (100)-WSe2 water interface, in which the electric dipole moment of water<br> molecules is re-oriented in a sort of 2-dimensional H-bond network. Bulk property calculations of WO3 and<br> WSe2 are also provided