Clays
We study clays, layered aluminosilicates minerals very abundant in nature, by molecular simulations, to understand the transport and retention properties of water and ions; what happens in the presence of CO2; or the dual hydrophilic/hydrophobic behaviour of talc surfaces. By ab initio simulations, we also estimate the acidity of the various edge surface sites.
During the PhD of Wilfried Louisfrema in collaboration with Anne Boutin (ENS), we also investigate ions in zeolites — aluminosilicates with a 3D nanoporosity. We consider in particular the case of heavy metal ions.
- Fundings : Andra, IFP-EN, ANR, DIM OXYMORE, France-Berkeley Fund
- PHENIX : Virginie Marry, Pierre Turq, Wilfried Louisfrema
- Collaborations : Marialore Sulpizi (Mainz), Michiel Sprik (Cambridge), David Chandler (Berkeley), Benoit Noetinger (IFP-EN), Anne Boutin (ENS)
Selected publications
- Molecular Simulation of CO2– and CO3-Brine-Mineral Systems
L.H. Hamm, I.C. Bourg, A.F. Wallace et B. Rotenberg, Rev. Mineral. Geochem., 77, 189 (2013)
- Absolute acidity of clay edge sites from ab-initio simulations
S. Tazi, B. Rotenberg, M. Salanne, M. Sprik and M. Sulpizi, Geochimica et Cosmochimica Acta, 94, 1 (2012)
- Molecular explanation for why talc surfaces can be both hydrophilic and hydrophobic
B. Rotenberg, A.J. Patel, D. Chandler, J. Am. Chem. Soc., 133, 20521 (2011)
- Carbon Dioxide in Montmorillonite Clay Hydrates : Thermodynamics, Structure, and Transport from Molecular Simulation
A. Botan, B. Rotenberg, V. Marry, P. Turq and B. Noetinger, J. Phys. Chem. C, 114, 14962 (2010)
- Water and ions in clays : Unraveling the interlayer/micropore exchange using molecular dynamics
B. Rotenberg, V. Marry, R. Vuilleumier, N. Malikova, C. Simon and P. Turq, Geochim. Cosmochim. Acta, 71, 5089 (2007)
Supercapacitors
We simulate ionic liquid confined between nanoporous carbon electrodes to uncover the microscopic origin of the high capacitance observed in supercapacitors. This allowed us to clarify the effects of confinement and (de)solvation on the charge storage properties. More recently, we investigated on the molecular scale the charging dynamics in these systems and made the link with simplified (equivalent circuits) models used in electrochemistry.
In order to address the effect of confinement, it is necessary to also study the case of planar electrodes (reference geometry). We have investigated several ionic liquids and the effect of solvation. In addition, we have demonstrated the importance of accounting for the electrode polarization to correctly describe these interfaces.
- Fundings: ANR
- PHENIX : Mathieu Salanne, Clarisse Péan
- Collaborations : Patrice Simon (Toulouse), Paul Madden (Oxford), Céline Merlet (Cambridge)
Selected publications
- On the dynamics of charging in nanoporous carbon-based supercapacitors
C. Péan, C. Merlet, B. Rotenberg, P.A. Madden, P.L. Taberna, B. Daffos, M. Salann et P. Simon, ACS Nano, 8 1576 (2014)
- Highly confined ions store charge more efficiently in supercapacitors
C. Merlet, C. Péan, B. Rotenberg, P.A. Madden, B. Daffos, P.-L. Taberna, P. Simon et M. Salanne, Nature Comm., 4, 2701 (2013)
- Computer simulations of ionic liquids at electrochemical interfaces
C. Merlet, B. Rotenberg, P.A. Madden et M. Salanne, Phys. Chem. Chem. Phys., 15, 15781 (2013)
- Simulating Supercapacitors : Can We Model Electrodes As Constant Charge Surfaces ?
C. Merlet, C. Péan, B. Rotenberg, P.A. Madden, P. Simon and M. Salanne, J. Phys. Chem. Lett., 4, 264 (2013)
- On the molecular origin of supercapacitance in nanoporous carbon electrodes
C. Merlet, B. Rotenberg, P.A. Madden, P.-L. Taberna, P. Simon, Y. Gogotsi et M. Salanne, Nature Mater., 11, 306 (2012)