PhD proposition at Local Probes and Sources Department

Subject : Nano electrodes in microfluidics: influence of the electric field on nucleation

Supervisors : Stéphane VEESLER et Nadine CANDONI

Contact : veesler@cinam.univ-mrs.fr / +33(0)6 62 92 28 66

Co-supervisors : Romain GROSSIER et Laurent LAPENA

 Description :

The importance of the first stages of crystallization (nucleation) on the control of the properties of materials in many fields such as mineralogy, biology or pharmacy is no longer to be demonstrated. The nucleation mechanisms behind crystallized products remain mysterious, mainly due to the fact that nucleation is of a stochastic nature: we do not know where and when an indefinite number of nucleation events will occur. This leads us to perform a large number of experiments, therefore droplet-based microfluidics is relevant in nucleation studies because it allows a large sample of independent and identical experiments. In recent years, studies on the triggering of nucleation by an external field have been carried out, but they are not very developed and mainly concern the use of lasers and very few on the application of an electric field.

We propose to couple nano electrodes to a microfluidics crystallization platform. The objective is to understand the effect of the localized electric field on nucleation, in order to propose new approaches for the crystallization of molecules that are difficult to crystallize.

 

The thesis will take place at CINaM in the “Local Probes and Sources” department, which has developed a strong expertise in localization of nucleation by application of a local and intense electric field1-2.   The experiments will be carried out on the microfluidics platform developed within the department3.

  1. Hammadi, Z.; Grossier, R.; Zhang, S.; Ikni, A.; Candoni, N.; Morin, R.; Veesler, S., Localizing and inducing primary nucleation. Faraday Discuss. 2015, 179, 489-501.
  2. Hammadi, Z.; Lapena, L.; Morin, R.; Olives, J., Immobilization of a bubble in water by nanoelectrolysis. Appl. Phys. Lett. 2016, 109 (6), 064101.
  3. Candoni, N.; Grossier, R.; Lagaize, M.; Veesler, S., Advances in the Use of Microfluidics to Study Crystallization Fundamentals. Annual Review of Chemical and Biomolecular Engineering 2019, 10 (1), 59-83.