Investigation of surface charge density on solid–liquid interfaces by modulating the electrical double layer

A solid surface in contact with water or aqueous solution usually carries specific electric charges. These surface charges attract counter ions from the liquid side. Since the geometry of opposite charge distribution parallel to the solid-liquid interface is similar to that of a capacitor, it is called an electrical double layer capacitor (EDLC). Therefore, there is an electrical potential difference across an EDLC in equilibrium. When a liquid bridge is formed between two conducting plates, the system behaves as two serially connected EDLCs. In this work, we propose a new method for investigating the surface charge density on solid-liquid interfaces. By mechanically modulating the electrical double layers and simultaneously applying a dc bias voltage across the plates, an ac electric current can be generated. By measuring the voltage drop across a load resistor as a function of bias voltage, we can study the surface charge density on solid-liquid interfaces. Our experimental results agree very well with the simple equivalent electrical circuit model proposed here. Furthermore, using this method, one can determine the polarity of the adsorbed state on the solid surface depending on the material used. We expect this method to aid in the study of electrical phenomena on solid-liquid interfaces.

[1]  F. Hoffmann,et al.  Infrared reflection-absorption spectroscopy of adsorbed molecules , 1983 .

[2]  R. F. Gouveia,et al.  Detection of charge distributions in insulator surfaces , 2009, Journal of physics. Condensed matter : an Institute of Physics journal.

[3]  M. Traisnel,et al.  The corrosion inhibition of mild steel in acidic media by a new triazole derivative , 1999 .

[4]  F. D. Schryver,et al.  Two-dimensional supramolecular self-assembly probed by scanning tunneling microscopy , 2003 .

[5]  Karen Willcox,et al.  Kinetics and kinematics for translational motions in microgravity during parabolic flight. , 2009, Aviation, space, and environmental medicine.

[6]  Pavel Jungwirth,et al.  Specific ion effects at the air/water interface. , 2006, Chemical reviews.

[7]  Michael A. Henderson,et al.  An HREELS and TPD study of water on TiO2(110): the extent of molecular versus dissociative adsorption , 1996 .

[8]  C. Haynes,et al.  Globular proteins at solid/liquid interfaces , 1994 .

[9]  Yves J. Chabal,et al.  Surface infrared spectroscopy , 1988 .

[10]  D. Grahame.  The electrical double layer and the theory of electrocapillarity. , 1947, Chemical reviews.

[11]  J. Israelachvili,et al.  The electrochemical surface forces apparatus: the effect of surface roughness, electrostatic surface potentials, and anodic oxide growth on interaction forces, and friction between dissimilar surfaces in aqueous solutions. , 2012, Langmuir : the ACS journal of surfaces and colloids.

[12]  Nichols,et al.  Atomic structure of Cu adlayers on Au(100) and Au(111) electrodes observed by in situ scanning tunneling microscopy. , 1990, Physical review letters.

[13]  M. Bazant,et al.  Diffuse-charge dynamics in electrochemical systems. , 2004, Physical review. E, Statistical, nonlinear, and soft matter physics.

[14]  Sirota,et al.  X-ray and neutron scattering from rough surfaces. , 1988, Physical review. B, Condensed matter.

[15]  Y. Shen,et al.  Surface properties probed by second-harmonic and sum-frequency generation , 1989, Nature.

[16]  S. Stankovich,et al.  Synthesis of graphene-based nanosheets via chemical reduction of exfoliated graphite oxide , 2007 .

[17]  E. Wang,et al.  Wettability of graphene. , 2013, Nano letters.

[18]  Y. Shen,et al.  Surface vibrational spectroscopy by infrared-visible sum frequency generation. , 1986, Physical review. B, Condensed matter.

[19]  B. Connors,et al.  Two networks of electrically coupled inhibitory neurons in neocortex , 1999, Nature.

[20]  D. Allara,et al.  Spontaneously organized molecular assemblies. 4. Structural characterization of n-alkyl thiol monolayers on gold by optical ellipsometry, infrared spectroscopy, and electrochemistry , 1987 .

[21]  H. Gaub,et al.  Molecular Organization of Surfactants at Solid-Liquid Interfaces , 1995, Science.

[22]  P. Renaud,et al.  Transport phenomena in nanofluidics , 2008 .

[23]  H. K. Wickramasinghe,et al.  Kelvin probe force microscopy , 1991 .

[24]  G. Fragneto-Cusani.  Neutron reflectivity at the solid/liquid interface : examples of applications in biophysics , 2001 .

[25]  G. Richmond,et al.  Molecular bonding and interactions at aqueous surfaces as probed by vibrational sum frequency spectroscopy. , 2002, Chemical reviews.

[26]  L. Carrette,et al.  Fuel Cells - Fundamentals and Applications , 2001 .

[27]  L. B. Harris,et al.  Vibrating capacitor measurement of surface charge , 1984 .

[28]  D. Aspnes,et al.  Investigation of effective-medium models of microscopic surface roughness by spectroscopic ellipsometry , 1979 .

[29]  J. Penfold,et al.  The application of the specular reflection of neutrons to the study of surfaces and interfaces , 1990 .

[30]  P. Marcus,et al.  Self-assembling of atomic vacancies at an oxide/intermetallic alloy interface , 2004, Nature materials.

[31]  Sergei V. Kalinin,et al.  Dual harmonic Kelvin probe force microscopy at the graphene-liquid interface , 2014 .

[32]  C. Berger,et al.  Electronic Confinement and Coherence in Patterned Epitaxial Graphene , 2006, Science.

[33]  Hyuk Kyu Pak,et al.  Electrical power generation by mechanically modulating electrical double layers , 2012, Nature Communications.

[34]  H. Gaub,et al.  Direct Visualization of Surfactant Hemimicelles by Force Microscopy of the Electrical Double-Layer , 1994 .

[35]  Paul Mulvaney,et al.  Surface Plasmon Spectroscopy of Nanosized Metal Particles , 1996 .

[36]  Hiroyuki Sugimura,et al.  Potential shielding by the surface water layer in Kelvin probe force microscopy , 2002 .

[37]  W. Henderson,et al.  Ionic liquids behave as dilute electrolyte solutions , 2013, Proceedings of the National Academy of Sciences.

[38]  A. Faisal,et al.  Noise in the nervous system , 2008, Nature Reviews Neuroscience.

[39]  A. Kulik,et al.  Spontaneous movement of ions through calcite at standard temperature and pressure , 1998, Nature.

[40]  F. Veer,et al.  Ellipsometry as a tool to study the adsorption behavior of synthetic and biopolymers at the air–water interface , 1978 .

[41]  D. Cyr,et al.  STM Investigations of Organic Molecules Physisorbed at the Liquid−Solid Interface , 1996 .

[42]  W. A. Zisman,et al.  A NEW METHOD OF MEASURING CONTACT POTENTIAL DIFFERENCES IN METALS , 1932 .

[43]  J. Israelachvili.  Intermolecular and surface forces , 1985 .

[44]  J. E. Stern,et al.  Contact electrification using force microscopy. , 1989, Physical review letters.

[45]  S. Baldelli,et al.  Sum frequency generation spectroscopy of the aqueous interface: Ionic and soluble molecular solutions , 2000 .

[46]  George M. Whitesides,et al.  Wet chemical approaches to the characterization of organic surfaces: self-assembled monolayers, wetting, and the physical-organic chemistry of the solid-liquid interface , 1990 .

[47]  K. Eisenthal,et al.  Liquid Interfaces Probed by Second-Harmonic and Sum-Frequency Spectroscopy. , 1996, Chemical reviews.

[48]  Roger Parsons,et al.  The electrical double layer: recent experimental and theoretical developments , 1990 .

[49]  Lord Kelvin,et al.  V. Contact electricity of metals , 1898 .

[50]  M. Urbakh,et al.  A model of electrowetting, reversed electrowetting, and contact angle saturation. , 2011, Langmuir : the ACS journal of surfaces and colloids.

[51]  P. Gennes.  Wetting: statics and dynamics , 1985 .

[52]  Daniel A. Higgins,et al.  Optical second harmonic generation as a probe of surface chemistry , 1994 .