Description of Hosting Institution (UJA – Spain)

Jaén University (UJA) was created in 1993 and is in the Top 50 of the world’s best young universities according to THE (Times Higher Education). This ranking analyzes aspects such as teaching, research work, the university’s international outreach, or integration into industry. Besides, the UJA has received the distinction of Campus of International Excellence in the fields of Agrifood (CEIA3) and Climate Change (CamBio), plus it also leads the Andalusian CEI project on historical heritage PatrimoniUN10.

Jaén University has five faculties (Social and Legal Sciences; Humanities and Education Sciences; Health Sciences; Experimental Sciences and Social Work) and two higher polytechnic schools for engineering (Linares and Jaén). In turn, these centers are organized into 35 departments. It also has three Postgraduate educational centers (Doctorate School, Advanced Study Center in Modern Languages and Postgraduate Study Center).

In regards to its research, there are several specialized centers at Jaén University (https://www.ujaen.es/servicios/ofipi/uja-ri-expertise). Besides, the full picture of the over 100 UJA groups covers the following research fields of expertise: Agrifood (AGR); Biology (BIO); Health (CTS); Social Sciences, Business, Law (SEJ); Physics, Chemistry, Mathematics (FQM); Humanities (HUM); Natural Resources and Environmental Sciences (RNM); Information and Communications Technology (TIC); and Engineering Production Technology (TEP).

As far this hosting offer is concerned, JOSÉ JUAN LÓPEZ GARCÍA would be willing to host post-doctoral researchers that are eventually funded through the MSCA-IF 2021 call for applications to be part of the following UJA research team: https://www.ujaen.es/servicios/ofipi/uja-ri-expertise/fqm-152-simulation-and-characterization-material-systems

Project description

The electric double layer (EDL), a globally electroneutral structure that builds up when a charged surface is placed in contact with an ionic solution, plays a fundamental role in all the systems where it appears. Electrokinetics is a general term associated with the relative motion between the two charged phases of the EDL. Thus, when the charged surface moves in one direction, the ions of the EDL in the solution undergo a net migration in the opposite one, causing thereby the movement of the solvent. The practical applications of these phenomena have become widespread in a broad range of research fields such as the regulation of selective ion transport through membranes and nanoporous channels, energy storage devices: electrochemical super condensers and batteries, and even energy generation using the free energy stored in two water sources with different salinity. This is why theoretical models for the interpretation of electrokinetic and dielectric phenomena are a subject of great interest. One of the main assumptions of the classical theory most widely used to characterize electrokinetic phenomena is that ions behave as point-like entities. While the realization of the importance of the finite ion size goes back to Stern, 1924, it was Bikerman who presented in 1942 the first expression for the steric interactions among ions. Even now, this is the most often used expression, mainly due to its analytic simplicity. However, once ions are considered to have a finite size, other consequences besides the steric interactions have to be considered. For example, the finite closest approach distance of ions to the interface, the dielectrophoretic force acting on ions in a non-uniform electric field, the variation of the electrolyte solution permittivity with the local ion concentration, and the corresponding Born force acting on the ions, have to be taken into account. Despite the important advances achieved in the last five years, we are still far away from a theoretical model capable to reliably reproduce most of the observed behaviors in systems where EDLs are present. Specifically, the applicant research group has achieved significant advances by means of a theoretical EDL model where ions are considered as dielectric spheres. The proposed model reproduces with high precision experimental measurements involving equilibrium EDLs at medium electric potential (or surface charge density) values. However, there is still a crucial step that is missing: the model validation for high electric potential (or surface charge) values and its extension to out of equilibrium situations. The objective of the submitted project is, therefore, the advancement towards a more realistic EDL model able to better characterize this kind of systems and to reliably predict their experimentally observed behavior.

Pre-application procedure

Interested applicants (PhD holders) should send their CV, Motivation letter and Summary of project proposal (250 words) to the UJA potential proposal supervisor (jjgarcia@ujaen.es) by the hosting offer deadline. Please, take into account that only candidates that meet the MSCA-IF 2021 application requirements according to the Funding & Tenders Portal (such as the so-called ‘mobility rule’) will be considered for proposal supervision.