Evidence of Epitaxial Growth of Molecular Layers of Dissolved Gas at a Hydrophobic/Water Interface

The non-wetting phenomena of water on certain solid surfaces have been under intensive study for decades, but the nature of hydrophobic/water interfaces remains controversial. Here a water/graphite interface is investigated with high-sensitivity atomic force microscopy. We show evidence of nucleation and growth of an epitaxial monolayer on the graphite surface, probably caused by adsorption of nitrogen molecules dissolved in water. The subsequent adsorption process resembles the layer-plus-island, or Stranski-Krastanov, growth mode in heteroepitaxy. This finding underlines the importance of gas segregation at various water interfaces and may unravel many puzzles, especially the nature and the high stability of so-called nanobubbles at solid/water interfaces and in bulk water. Based on the hydrophobic effect, we propose that gas molecules dissolved in water may aggregate into clusters in bulk water as well as at solid/water interfaces. As a cluster grows above a critical size, it undergoes a transition into a gas bubble, which can explain formation or nucleation of gas bubbles in water.

[1]  U. Schwarz,et al.  Noncontact atomic force microscopy , 2012, Beilstein journal of nanotechnology.

[2]  W. Zimmerman,et al.  Towards energy efficient nanobubble generation with fluidic oscillation , 2011 .

[3]  M. Doherty,et al.  Communication: Bubbles, crystals, and laser-induced nucleation. , 2011, The Journal of chemical physics.

[4]  S. Oshita,et al.  Transmission electron microscopic observations of nanobubbles and their capture of impurities in wastewater , 2011, Nanoscale research letters.

[5]  D. Lohse,et al.  Nanobubbles and micropancakes: gaseous domains on immersed substrates , 2011, Journal of physics. Condensed matter : an Institute of Physics journal.

[6]  V. Craig.  Very small bubbles at surfaces—the nanobubble puzzle , 2011 .

[7]  Haiping Fang,et al.  The length scales for stable gas nanobubbles at liquid/solid surfaces , 2010 .

[8]  S. Oshita,et al.  Evidence of the existence and the stability of nano-bubbles in water , 2010 .

[9]  Zhong-Zhen Yu,et al.  Superhydrophobic to Superhydrophilic Wetting Control in Graphene Films , 2010, Advanced materials.

[10]  P. Dutta,et al.  How water meets a very hydrophobic surface. , 2010, Physical review letters.

[11]  Kazunari Ohgaki,et al.  Physicochemical approach to nanobubble solutions , 2010 .

[12]  Y. Shen,et al.  Structure and charging of hydrophobic material/water interfaces studied by phase-sensitive sum-frequency vibrational spectroscopy , 2009, Proceedings of the National Academy of Sciences.

[13]  D. Lohse,et al.  Electrolytically generated nanobubbles on highly orientated pyrolytic graphite surfaces. , 2009, Langmuir : the ACS journal of surfaces and colloids.

[14]  N. Maeda,et al.  Thermodynamic stability of interfacial gaseous states. , 2008, The journal of physical chemistry. B.

[15]  Xuehua Zhang,et al.  Nanobubbles at the interface between water and a hydrophobic solid. , 2008, Langmuir : the ACS journal of surfaces and colloids.

[16]  Kaneo Chiba,et al.  Free-radical generation from collapsing microbubbles in the absence of a dynamic stimulus. , 2007, The journal of physical chemistry. B.

[17]  M. Grunze,et al.  Density depletion at solid-liquid interfaces: a neutron reflectivity study. , 2007, Langmuir : the ACS journal of surfaces and colloids.

[18]  Haiping Fang,et al.  Detection of novel gaseous states at the highly oriented pyrolytic graphite-water interface. , 2006, Langmuir : the ACS journal of surfaces and colloids.

[19]  D. Palms,et al.  High-resolution in situ x-ray study of the hydrophobic gap at the water–octadecyl-trichlorosilane interface , 2006, Proceedings of the National Academy of Sciences.

[20]  J. Israelachvili,et al.  Recent progress in understanding hydrophobic interactions , 2006 .

[21]  M. Aratono,et al.  Ellipsometric search for vapor layers at liquid-hydrophobic solid surfaces. , 2006, Langmuir : the ACS journal of surfaces and colloids.

[22]  D. Lohse,et al.  Gas enrichment at liquid-wall interfaces. , 2005, Physical review letters.

[23]  D. Chandler.  Interfaces and the driving force of hydrophobic assembly , 2005, Nature.

[24]  J. Israelachvili,et al.  Reduced water density at hydrophobic surfaces: effect of dissolved gases. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[25]  W. Ducker,et al.  Is there a Thin Film of Air at the Interface between Water and Smooth Hydrophobic Solids , 2004 .

[26]  Franz J. Giessibl,et al.  Advances in atomic force microscopy , 2003, cond-mat/0305119.

[27]  James W. G. Tyrrell,et al.  Images of nanobubbles on hydrophobic surfaces and their interactions. , 2001, Physical review letters.

[28]  Z. Ogumi,et al.  Hydrogen particles and supersaturation in alkaline water from an Alkali-Ion-Water electrolyzer , 2001 .

[29]  M Levitt,et al.  Quantification of the hydrophobic interaction by simulations of the aggregation of small hydrophobic solutes in water , 2001, Proceedings of the National Academy of Sciences of the United States of America.

[30]  Yi Zhang,et al.  Nanobubbles on solid surface imaged by atomic force microscopy , 2000 .

[31]  Masanobu Sakamoto,et al.  Attraction between hydrophobic surfaces with and without gas phase , 2000 .

[32]  T. Tsong,et al.  Growth mechanism and morphology of Ge on Pb covered Si (111) surfaces , 1998 .

[33]  Jan Christer Eriksson,et al.  The lifetime of a colloid-sized gas bubble in water and the cause of the hydrophobic attraction , 1997 .

[34]  Phil Attard,et al.  BUBBLES, CAVITIES, AND THE LONG-RANGED ATTRACTION BETWEEN HYDROPHOBIC SURFACES , 1994 .

[35]  H. Jehn.  Nucleation and Growth of Thin Films , 1992 .

[36]  J. Israelachvili,et al.  Measurement of the hydrophobic interaction between two hydrophobic surfaces in aqueous electrolyte solutions , 1984 .

[37]  J. Israelachvili,et al.  The hydrophobic interaction is long range, decaying exponentially with distance , 1982, Nature.