Adsorption, diffusion, dewetting, and entrapment of acetone on Ni(111), surface-modified silicon, and amorphous solid water studied by time-of-flight secondary ion mass spectrometry and temperature programmed desorption.

Interactions of acetone with the silicon surfaces terminated with hydrogen, hydroxyl, and perfluorocarbon are investigated; results are compared to those on amorphous solid water (ASW) to gain insights into the roles of hydrogen bonds in surface diffusion and hydration of acetone adspecies. The surface mobility of acetone occurs at ∼60 K irrespective of the surface functional groups. Cooperative diffusion of adspecies results in a 2D liquid phase on the H- and perfluorocarbon-terminated surfaces, whereas cooperativity tends to be quenched via hydrogen bonding on the OH-terminated surface, thereby forming residues that diffuse slowly on the surface after evaporation of the physisorbed species (i.e., 2D liquid). The interaction of acetone adspecies on the non-porous ASW surface resembles that on the OH-terminated Si surface, but the acetone molecules tend to be hydrated on the porous ASW film, as evidenced by their desorption during the glass-liquid transition and crystallization of water. The roles of micropores in hydration of acetone molecules are discussed from comparison with the results using mesoporous Si substrates.