TY - JOUR
T1 - Influence of Hydrogen Bonding between Ions of like Charge on the Ionic Liquid Interfacial Structure at a Mica Surface
AU - Niemann, Thomas
AU - Li, Hua
AU - Warr, Gregory G.
AU - Ludwig, Ralf
AU - Atkin, Rob
PY - 2019/12/5
Y1 - 2019/12/5
N2 - Ionic liquids (ILs) have attracted increasing interest in science and technology because of their remarkable properties, which can be tuned via varying ion structures to control the relative strengths of Coulomb interactions, hydrogen bonding (H-bonding), and dispersion forces. Here we use atomic force microscopy to probe the interfacial nanostructures of hydroxy functionalized ILs at negatively charged mica surfaces. H-bonding between hydroxy functionalized cations (c-c) produces cation clusters and a stronger interfacial nanostructure. H-bond stabilized cation clusters form despite opposing electrostatic repulsions between charge groups, cation-anion (c-a) electrostatic attractions, and (c-a) H-bonds. Comparison of ILs with and without OH functionalized cations shows directional H-bonding enhances interfacial structure more strongly than the dispersion forces between alkyl groups. These findings reveal a new means of controlling IL interfacial nanostructure via H-bonding between like-charged ions, which impact diverse areas including electrochemical charge storage (batteries and catalysis), electrodeposition, lubrication, etc.
AB - Ionic liquids (ILs) have attracted increasing interest in science and technology because of their remarkable properties, which can be tuned via varying ion structures to control the relative strengths of Coulomb interactions, hydrogen bonding (H-bonding), and dispersion forces. Here we use atomic force microscopy to probe the interfacial nanostructures of hydroxy functionalized ILs at negatively charged mica surfaces. H-bonding between hydroxy functionalized cations (c-c) produces cation clusters and a stronger interfacial nanostructure. H-bond stabilized cation clusters form despite opposing electrostatic repulsions between charge groups, cation-anion (c-a) electrostatic attractions, and (c-a) H-bonds. Comparison of ILs with and without OH functionalized cations shows directional H-bonding enhances interfacial structure more strongly than the dispersion forces between alkyl groups. These findings reveal a new means of controlling IL interfacial nanostructure via H-bonding between like-charged ions, which impact diverse areas including electrochemical charge storage (batteries and catalysis), electrodeposition, lubrication, etc.
UR - http://www.scopus.com/inward/record.url?scp=85075615465&partnerID=8YFLogxK
U2 - 10.1021/acs.jpclett.9b03007
DO - 10.1021/acs.jpclett.9b03007
M3 - Article
C2 - 31713427
AN - SCOPUS:85075615465
SN - 1948-7185
VL - 10
SP - 7368
EP - 7373
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
IS - 23
ER -