Milton Katherine L, Hargreaves Laura, Shluger Alexander
Department of Physics and Astronomy and the London Centre for Nanotechnology, University College London, Gower Street, London WC1E 6BT, U.K.
WPI-Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, 21-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.
J Phys Chem C Nanomater Interfaces. 2025 Feb 17;129(8):4261-4271. doi: 10.1021/acs.jpcc.4c08392. eCollection 2025 Feb 27.
The WS/SiO interface is of interest to a variety of research communities due to the electronic properties of WS and the ubiquity of SiO as a dielectric substrate. Due to the hydrophilic nature of silanol groups on the surface of SiO, water is difficult to remove at the surface, leading to confined water between WS and SiO. Understanding the properties of confined water is important both fundamentally and for their effects on the interfacing materials. We investigated the structure and dynamics of confined water between WS and SiO using density functional theory and molecular dynamics, comparing it to adsorbed water on the surfaces of WS and SiO. The results show that confined water becomes increasingly structured, with its orientation influenced by hydrogen bonding to the silanol groups as well as by the partial reorientation of water molecules to face WS in an H-up configuration. The presence of silanol groups disrupts the hydrogen bonding network of water at monolayer coverage for both confined and unconfined water. For all interfaces explored, changes in both structural and dynamic properties are dependent on the number of water layers present.
由于WS的电子特性以及SiO作为介电基板的普遍性，WS/SiO界面受到了各种研究群体的关注。由于SiO表面硅醇基团的亲水性，水在表面难以去除，导致WS和SiO之间存在受限水。了解受限水的性质在基础研究以及其对界面材料的影响方面都很重要。我们使用密度泛函理论和分子动力学研究了WS和SiO之间受限水的结构和动力学，并将其与WS和SiO表面吸附的水进行了比较。结果表明，受限水的结构越来越规整，其取向受与硅醇基团的氢键作用以及水分子部分重新取向以H向上构型面向WS的影响。硅醇基团破坏了受限水和非受限水在单层覆盖时水的氢键网络。对于所有探索的界面，结构和动力学性质的变化都取决于存在的水层数。
