Seminars

PMMH’s weekly seminar is held every Friday at 11 am (map)

Contact :
Stéphane Perrard
Etienne Reyssat
Virgile Thiévenaz
responsables-seminaires (arobase) pmmh.espci.fr

PMMH
BARRE CASSAN
BAT A 1ER ETAGE CASE 18
7 QUAI SAINT BERNARD
75005 PARIS
France

Tel : (33) 1 40 79 45 22


Séminaire PMMH - Vince Craig, Australian National University, Australia

Vendredi 11 juillet de 11h00 à 12h00 - Salle réunion PMMH 1

Underscreening Stable colloidal systems at very high electrolyte concentrations

In colloidal systems the range and strength of electrostatic interactions has a profound effect on a range of properties including the stability of colloidal dispersions and the phase behaviour of surfactant and polymer systems. The Debye length has proven to be a very effective measure of the range of electrostatic interactions as confirmed by direct force measurements at low to moderate salt concentrations over many years . However, recent force measurements on ionic liquid systems has revealed that at high electrolyte concentration the electrostatic interactions are much longer ranged than the Debye length[1-5]. This has implications for all colloidal systems at high electrolyte concentrations.

In this talk I will describe a series of experiments probing the impact of underscreening on colloidal systems and discuss the current state of understanding of the origin of underscreening.

References

[1] M.A. Gebbie, M. Valtiner, X. Banquy, E.T. Fox, W.A. Henderson, J.N. Israelachvili, Ionic liquids behave as dilute electrolyte solutions, Proc. Nat. Acad. Sci. 110(24) (2013) 9674-9679.
[2] A.M. Smith, A.A. Lee, S. Perkin, The Electrostatic Screening Length in Concentrated Electrolytes Increases with Concentration, J. Phys. Chem. Lett. 7(12) (2016) 2157-2163.
[3] M.A. Gebbie, A.M. Smith, H.A. Dobbs, A.A. Lee, G.G. Warr, X. Banquy, M. Valtiner, M.W. Rutland, J.N. Israelachvili, S. Perkin, R. Atkin, Long range electrostatic forces in ionic liquids, Chem. Commun. 53(7) (2017) 1214-1224.
[4] A.A. Lee, C.S. Perez-Martinez, A.M. Smith, S. Perkin, Scaling Analysis of the Screening Length in Concentrated Electrolytes, Phys. Rev. Lett. 119 (2017) 026002.
[5] A.A. Lee, C.S. Perez-Martinez, A.M. Smith, S. Perkin, Underscreening in concentrated electrolytes, Faraday Discuss. 199 (2017) 239-259.

Top







Seminars  (0)

Information for the speakers

The audience is composed of people with rather heterogeneous backgrounds including specialists in solids, fluids, granular flows, statistical physics... so the idea is to keep your talk understandable by people not necessarily working in your field... The seminar time slot runs from 11am to noon so the best is to make the talk last around 45 minutes to leave some time for discussion.

Link to cofee seminar (internal, every Thursday)


Top



Contact

Directeur : Ramiro GODOY DIANA
Codirecteur : Laurent DUCHEMIN
Administratrice : Frédérique AUGER (01 40 79 45 22)
Gestionnaire : Claudette BAREZ (01 40 79 58 53)
Courriel : dir (arobase) pmmh.espci.fr
Téléphone : 01 40 79 45 22