Molecular layer of gaslike domains at a hydrophobic-water interface observed by frequency-modulation atomic force microscopy.
It was numerically predicted that dissolved gas particles could enrich and adsorb at hydrophobic-liquid interfaces. Here we observe nucleation and growth of bright patches of ∼0.45 nm high on the graphite surface in pure water with frequency-modulation atomic force microscopy when the dissolved gas concentration is below the saturation level. The bright patches, suspected to be caused by adsorption of nitrogen molecules at the graphite-water interface, are composed of domains of a rowlike structure with the row separation of 4.2 ± 0.3 nm. The observation of this ordered adlayer might underline the gas segregation at various water interfaces.
Institute of Physics, Academia Sinica, Nankang, Taipei 115, Taiwan.
Yi-Hsien
YH
Lu
Chih-Wen
CW
Yang
Ing-Shouh
IS
Hwang
D000327:Adsorption; D002244:Carbon / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D018625:Microscopy, Atomic Force; D009584:Nitrogen / Q000737:chemistry*; D013499:Surface Properties; D014867:Water / Q000737:chemistry*
C009139:pyrolytic carbon; D014867:Water; D002244:Carbon; D006108:Graphite; D009584:Nitrogen