文献类型：期刊文献

英文题名：Room temperature bilayer water structures on a rutile TiO2(110) surface: hydrophobic or hydrophilic?

作者：Qu, Mengyang[1,2];Huang, Gang[4];Liu, Xinyi[3];Nie, Xuechuan[1,2];Qi, Chonghai[1];Wang, Huabin[5];Hu, Jun[1,6];Fang, Haiping[7];Gao, Yi[1,6];Liu, Wei-Tao[3];Francisco, Joseph S.[8,9];Wang, Chunlei[1,6]

机构：[1]Chinese Acad Sci, Shanghai Inst Appl Phys, Shanghai 201800, Peoples R China;[2]Univ Chinese Acad Sci, Beijing 100049, Peoples R China;[3]Fudan Univ, Dept Phys, Shanghai 200433, Peoples R China;[4]Chinese Acad Sci, Inst Theoret Phys, Zhongguancun East Rd 55, Beijing 100190, Peoples R China;[5]Chinese Acad Sci, Chongqing Inst Green & Intelligent Technol, Chongqing 400714, Peoples R China;[6]Chinese Acad Sci, fZhangjiang Lab, Interdisplinary Res Ctr, Shanghai Adv Res Inst, Shanghai 201210, Peoples R China;[7]East China Univ Sci & Technol, Sch Sci, Shanghai 200237, Peoples R China;[8]Univ Penn, Dept Earth & Envimnmental Sci, Philadelphia, PA 19104 USA;[9]Univ Penn, Dept Chem, Philadelphia, PA 19104 USA

年份：2022

卷号：13

期号：35

起止页码：10546

外文期刊名：CHEMICAL SCIENCE

收录：;EI(收录号：20223612678878);WOS:【SCI-EXPANDED(收录号:WOS:000844794000001)】；

基金：This study was supported by the National Natural Science Foundation of China (Nos. 12022508, 12074394, 11991062 and 11674345) and CAS Scholarship and Shanghai Supercomputer Center of China.

语种：英文

外文关键词：Contact angle - Hydrogen bonds - Hydrophobicity - Molecular dynamics - Molecules - Organic pollutants - Oxide minerals - Wetting

摘要：The lack of understanding of the molecular-scale water adsorbed on TiO2 surfaces under ambient conditions has become a major obstacle for solving the long-time scientific and applications issues, such as the photo-induced wetting phenomenon and designing novel advanced TiO2-based materials. Here, with the molecular dynamics simulation, we identified an ordered water bilayer structure with a two-dimensional hydrogen bonding network on a rutile TiO2(110) surface at ambient temperature, corroborated by vibrational sum-frequency generation spectroscopy. The reduced number of hydrogen bonds between the water bilayer and water droplet results in a notable water contact angle (25 +/- 5 degrees) of the pristine TiO2 surface. This surface hydrophobicity can be enhanced by the adsorption of the formate/acetate molecules, and diminishes with dissociated H2O molecules. Our new physical framework well explained the long-time controversy on the origin of the hydrophobicity/hydrophilicity of the TiO2 surface, thus help understanding the efficiency of TiO2 devices in producing electrical energy of solar cells and the photo-oxidation of organic pollutants.