Atomically resolved interfacial water structures on crystalline hydrophilic and hydrophobic surfaces

Autor: Simone Benaglia, Ravindra Thakkar, Jeffrey Comer, Manuel R. Uhlig, Ricardo Garcia
Přispěvatelé: European Research Council, Ministerio de Ciencia, Innovación y Universidades (España), European Commission, National Science Foundation (US), Ministerio de Economía y Competitividad (España), Uhlig, Manuel R., Benaglia, Simone, Comer, Jeffrey, García-García, Ricardo, Uhlig, Manuel R. [0000-0002-7313-7572], Benaglia, Simone [0000-0001-8997-0967], Comer, Jeffrey [0000-0003-4437-1260], García-García, Ricardo [0000-0002-7115-1928]
Rok vydání: 2021
Předmět:
Zdroj: Digital.CSIC. Repositorio Institucional del CSIC
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Popis: [EN] Hydration layers are formed on hydrophilic crystalline surfaces immersed in water. Their existence has also been predicted for hydrophobic surfaces, yet the experimental evidence is controversial. Using 3D-AFM imaging, we probed the interfacial water structure of hydrophobic and hydrophilic surfaces with atomic-scale spatial resolution. We demonstrate that the atomic-scale structure of interfacial water on crystalline surfaces presents two antagonistic arrangements. On mica, a common hydrophilic crystalline surface, the interface is characterized by the formation of 2 to 3 hydration layers separated by approximately 0.3 nm. On hydrophobic surfaces such as graphite or hexagonal boron nitride (h-BN), the interface is characterized by the formation of 2 to 4 layers separated by about 0.5 nm. The latter interlayer distance indicates that water molecules are expelled from the vicinity of the surface and replaced by hydrocarbon molecules. This creates a new 1.5-2 nm thick interface between the hydrophobic surface and the bulk water. Molecular dynamics simulations reproduced the experimental data and confirmed the above interfacial water structures. This journal is
European Research Council ERC-AdG-340177, the Ministerio de Ciencia, Innovación y Universidades (PID2019- 106801GB-I00; MAT2016-76507-R) and European Commission Marie Sklodowska-Curie grant agreement No. 721874. J.C. acknowledges financial support by the US National Science Foundation under Grant No. CHE-1726332 and DMR-1945589.
Databáze: OpenAIRE