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PhD subjects

4 sujets IRAMIS

Dernière mise à jour : 24-06-2018


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• Physical chemistry and electrochemistry

 

Catalytic activity of Platinum-free active layers for Proton Exchange Membrane Fuel Cells (PEMFC)

SL-DRF-18-0895

Research field : Physical chemistry and electrochemistry
Location :

Service Nanosciences et Innovation pour les Materiaux, la Biomédecine et l'Energie

Laboratoire Innovation, Chimie des Surfaces Et Nanosciences

Saclay

Contact :

Renaud CORNUT

Bruno JOUSSELME

Starting date : 01-09-2018

Contact :

Renaud CORNUT

CEA - DRF/IRAMIS/NIMBE/LICSEN

01 69 08 91 91

Thesis supervisor :

Bruno JOUSSELME

CEA - DRF/IRAMIS/NIMBE/LICSEN

0169 08 91 91

Personal web page : http://iramis.cea.fr/Pisp/renaud.cornut/

Laboratory link : http://iramis.cea.fr/nimbe/licsen/

The future of energy supply depends on innovative breakthroughs regarding the design of efficient systems for the conversion and storage of energy. In this field, electrocatalytic systems are at the cornerstone of many related challenges in fuel cells since they offer suitable solutions for performing very complex reactions. The present project introduces an original strategy based on Scanning Electrochemical Microscopy (SECM)and numerical simulation for the finding of low cost elementary bricks used to form electrocatalytic layers through the combined analysis of individual nano-objects. It will permit to find new electrocatalytic species, and this will lead to electrocatalytic layers having improved performances.

Electrochemical microscopy investigation of the multiphasic transport within an electrocatalytique layer

SL-DRF-18-0442

Research field : Physical chemistry and electrochemistry
Location :

Service Nanosciences et Innovation pour les Materiaux, la Biomédecine et l'Energie

Laboratoire Innovation, Chimie des Surfaces Et Nanosciences

Saclay

Contact :

Renaud CORNUT

Bruno JOUSSELME

Starting date : 01-09-2018

Contact :

Renaud CORNUT

CEA - DRF/IRAMIS/NIMBE/LICSEN

01 69 08 91 91

Thesis supervisor :

Bruno JOUSSELME

CEA - DRF/IRAMIS/NIMBE/LICSEN

0169 08 91 91

Personal web page : http://iramis.cea.fr/Pisp/renaud.cornut/

Laboratory link : http://iramis.cea.fr/nimbe/licsen/

The emergence of hydrogen as an energy vector must help to stop pollution issued from the use of carbon-based energy sources in transport. In vehicles the conversion to electricity is achieved with proton exchange membrane fuel cells.



The aim of the project is to make them compatible with mass market by providing competitive cathodes containing inexpensive catalytic nano-objects. A huge diversity of starting materials, combinations of materials and processing conditions are possible, and identifying the optimal strategy at each step is presently very challenging. To manage this, we first set up an electroanalytical platform to evaluate in routine the effective electrochemical properties of multifunctional materials used in fuel cells. We then produce many different materials in a combinatorial fashion, the analysis of which permits to understand the way nano-objects assemble into electrocatalytic materials. From this, we rationalize the different processing steps and optimize the performances, with special care to the ageing of the materials.

Multi-scale and conformation-resolved dynamics of the electronic relaxation in flexible molecules

SL-DRF-18-0775

Research field : Physical chemistry and electrochemistry
Location :

Service Laboratoire Interactions, Dynamique et Lasers

Saclay

Contact :

Lionel POISSON

Eric GLOAGUEN

Starting date : 01-10-2018

Contact :

Lionel POISSON

CNRS-UMR9222 - DSM/IRAMIS/LIDYL/DYR

01 69 08 51 61

Thesis supervisor :

Eric GLOAGUEN

CNRS - DSM/IRAMIS/LIDyL/SBM

01 69 08 35 82

Personal web page : http://iramis.cea.fr/Pisp/34/lionel.poisson.html

Laboratory link : http://iramis.cea.fr/LIDYL/index.php

More : http://iramis.cea.fr/Pisp/70/eric.gloaguen.html

Flexible molecules are ubiquitous in Nature (proteins, sugars, ...) and are at the origin of many applications (drugs, molecular machines, ...). By definition, these molecules exist in several conformations that each have physical, chemical or biological properties which can vary greatly from one conformation to another. Among these properties, photoexcitation and relaxation of the electronic states are particularly sensitive to conformation: for example, the lifetime of the first excited electronic state can vary with the conformation by several orders of magnitude. However, the experimental characterisation of such conformational effects on the excited states remains rare due to the difficulty to specifically study one conformation present in a conformational mixture. This thematic is still poorly documented despite i) a need for experimental results to help the development of theoretical models, and ii) a lack of knowledge in a field where fundamental (conical intersections, ultrafast phenomena) and application (photostability, energy transfer) issues are important.



In this context, the LIDYL laboratory brings together several experimental apparatus allowing an original multi-scale (ns-fs) and conformation-resolved study of the dynamics of the electronic relaxation in flexible molecular systems. The research program will focus on biologically-relevant systems and molecular complexes, and will target:



- the observation of conformer-dependent dynamic processes and their rationalisation.

- the characterization of species previously inaccessible to conventional detection techniques.

High Energy Supercapacitors and pseudo-supercapacitors based on p- and n-dopable materials

SL-DRF-18-0799

Research field : Physical chemistry and electrochemistry
Location :

Service Nanosciences et Innovation pour les Materiaux, la Biomédecine et l'Energie

Laboratoire Edifices Nanométriques

Saclay

Contact :

Mathieu PINAULT

Starting date : 01-10-2018

Contact :

Mathieu PINAULT

CEA - DRF/IRAMIS/NIMBE/LEDNA

01-69-08-91-87

Thesis supervisor :

Mathieu PINAULT

CEA - DRF/IRAMIS/NIMBE/LEDNA

01-69-08-91-87

Personal web page : http://iramis.cea.fr/Pisp/mathieu.pinault/

Laboratory link : http://iramis.cea.fr/nimbe/ledna/

More : https://www.u-cergy.fr/fr/laboratoires/lppi/themes-de-recherche/theme-ii.html

The aerosol-assisted CVD method (Chemical Vapor Deposition) developed at CEA Saclay provides dense mats of vertically aligned carbon nanotubes (VACNT) especially on aluminum support. The applications of these nanostructured materials are particularly promising in the field of electrochemical energy storage using either nanotubes alone (targeted application power) or by associating them with electronically conductive polymers (PCE, targeted energy application). In collaboration with the University of Cergy-Pontoise (Laboratoire LPPI), we will improve the performances by working on electrode materials. Significant advances have already been made on the positive electrode and the objective is now to work on the negative one and in particular on the doping of the various elements or post treatments. We will first develop controlled growth of VACNT containing heteroatoms (N, B) on substrates of interest for the elaboration of supercapacitor electrodes while controlling their characteristics (length, diameter, density). In parallel, we will associate the VACNT with n-doped ECP through electrochemical deposition. These new nanostructured electrodes will be studied and associated to realize supercapacitors in the form of coin cell in order to determine their Energy/Power performances.

 

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