Nature of the Electrical Double Layer on Suspended Graphene Electrodes

The structure of interfacial water near suspended graphene electrodes in contact with aqueous solutions of Na2SO4, NH4Cl, and (NH4)2SO4 has been studied using confocal Raman spectroscopy, sum frequency vibrational spectroscopy, and Kelvin probe force microscopy. SO42– anions were found to preferentially accumulate near the interface at an open circuit potential (OCP), creating an electrical field that orients water molecules below the interface, as revealed by the increased intensity of the O–H stretching peak of H-bonded water. No such increase is observed with NH4Cl at the OCP. The intensity of the dangling O–H bond stretching peak however remains largely unchanged. The degree of orientation of the water molecules as well as the electrical double layer strength increased further when positive voltages are applied. Negative voltages on the other hand produced only small changes in the intensity of the H-bonded water peaks but affected the intensity and frequency of dangling O–H bond peaks. The TOC figure is an oversimplified representation of the system in this work.

[1]  M. Koper,et al.  Double-layer structure of the Pt(111)–aqueous electrolyte interface , 2022, Proceedings of the National Academy of Sciences.

[2]  M. Head‐Gordon,et al.  Stripping away ion hydration shells in electrical double-layer formation: Water networks matter , 2021, Proceedings of the National Academy of Sciences.

[3]  W. Goddard,et al.  Entropic Stabilization of Water at Graphitic Interfaces. , 2021, The journal of physical chemistry letters.

[4]  S. Cronin,et al.  Asymmetric response of interfacial water to applied electric fields , 2021, Nature.

[5]  A. Sirota,et al.  Graphene active sensor arrays for long-term and wireless mapping of wide frequency band epicortical brain activity , 2021, Nature Communications.

[6]  D. F. Ogletree,et al.  Ultra-thin Free-Standing Oxide Membranes for Electron and Photon Spectroscopy Studies of Solid-gas and Solid-liquid Interfaces. , 2020, Nano letters.

[7]  G. Schneider,et al.  Wettability of graphene , 2020, Surface Science Reports.

[8]  M. Bonn,et al.  Kinetic Ionic Permeation and Interfacial Doping of Supported Graphene , 2019, Nano letters.

[9]  Carly V. Fengel,et al.  Hall Effect Measurements of the Double-Layer Capacitance of the Graphene–Electrolyte Interface , 2019, The Journal of Physical Chemistry C.

[10]  H. Bechtel,et al.  Infrared Nanospectroscopy at the Graphene-Electrolyte Interface. , 2019, Nano letters.

[11]  B. Mi.  Scaling up nanoporous graphene membranes , 2019, Science.

[12]  M. Otyepka,et al.  Ion Interactions across Graphene in Electrolyte Aqueous Solutions , 2019, The Journal of Physical Chemistry C.

[13]  A. Temiryazev,et al.  Atomic-force microscopy study of self-assembled atmospheric contamination on graphene and graphite surfaces , 2019, Carbon.

[14]  D. Prendergast,et al.  Exploring chemical speciation at electrified interfaces using detailed continuum models. , 2019, The Journal of chemical physics.

[15]  Wanlin Guo,et al.  Emerging hydrovoltaic technology , 2018, Nature Nanotechnology.

[16]  Yuki Nagata,et al.  Structure and dynamics of water at water-graphene and water-hexagonal boron-nitride sheet interfaces revealed by ab initio sum-frequency generation spectroscopy. , 2018, Physical chemistry chemical physics : PCCP.

[17]  M. Raschke,et al.  Mechanism of Electric Power Generation from Ionic Droplet Motion on Polymer Supported Graphene. , 2018, Journal of the American Chemical Society.

[18]  D. Mayer,et al.  Biosensing near the neutrality point of graphene , 2017, Science Advances.

[19]  G. Schneider,et al.  Sensing at the Surface of Graphene Field‐Effect Transistors , 2017, Advanced materials.

[20]  Christopher D. Williams,et al.  Effective Polarization in Pair-Wise Potentials at the Graphene-Electrolyte Interface. , 2017, The journal of physical chemistry letters.

[21]  Cees Dekker,et al.  Graphene nanodevices for DNA sequencing. , 2016, Nature nanotechnology.

[22]  G. Somorjai,et al.  In Situ Potentiodynamic Analysis of the Electrolyte/Silicon Electrodes Interface Reactions--A Sum Frequency Generation Vibrational Spectroscopy Study. , 2016, Journal of the American Chemical Society.

[23]  John A. Williams,et al.  Time Evolution of the Wettability of Supported Graphene under Ambient Air Exposure , 2016, The journal of physical chemistry. C, Nanomaterials and interfaces.

[24]  G. Ohanessian,et al.  Hydration of the sulfate dianion in cold nanodroplets: SO4(2-)(H2O)12 and SO4(2-)(H2O)13. , 2015, Physical chemistry chemical physics : PCCP.

[25]  Yaochun Shen,et al.  Polymer Adsorption on Graphite and CVD Graphene Surfaces Studied by Surface-Specific Vibrational Spectroscopy. , 2015, Nano letters.

[26]  D. Tobias,et al.  Toward a unified picture of the water self-ions at the air-water interface: a density functional theory perspective. , 2014, The journal of physical chemistry. B.

[27]  Wanlin Guo,et al.  Waving potential in graphene , 2014, Nature Communications.

[28]  Wanlin Guo,et al.  Generating electricity by moving a droplet of ionic liquid along graphene. , 2014, Nature nanotechnology.

[29]  C Raillon,et al.  Detecting the translocation of DNA through a nanopore using graphene nanoribbons. , 2013, Nature nanotechnology.

[30]  Haitao Liu,et al.  Effect of airborne contaminants on the wettability of supported graphene and graphite. , 2013, Nature materials.

[31]  D. Neumark,et al.  Infrared Spectroscopy of Hydrated Bisulfate Anion Clusters: HSO4¯(H2O)1–16 , 2011 .

[32]  K. Loh,et al.  Ion Adsorption at the Graphene/Electrolyte Interface , 2011 .

[33]  Cees Dekker,et al.  Influence of electrolyte composition on liquid-gated carbon nanotube and graphene transistors. , 2010, Journal of the American Chemical Society.

[34]  A. Reina,et al.  Graphene as a sub-nanometer trans-electrode membrane , 2010, Nature.

[35]  Y. Ohno,et al.  Electrolyte-gated graphene field-effect transistors for detecting pH and protein adsorption. , 2009, Nano letters.

[36]  Priscilla Kailian Ang,et al.  Solution-gated epitaxial graphene as pH sensor. , 2008, Journal of the American Chemical Society.

[37]  D. Neumark,et al.  Infrared spectroscopy of hydrated sulfate dianions. , 2006, The Journal of chemical physics.

[38]  H. Allen,et al.  Air-liquid interfaces of aqueous solutions containing ammonium and sulfate: spectroscopic and molecular dynamics studies. , 2005, The journal of physical chemistry. B.