PhD thesis defense of Nesrine HARFOUCHE

Nesrine HARFOUCHE, PhD student at MAPIEM lab, under the supervision of:

• M. Belkacem NESSARK, Pr, University of Sétif 1 (Algeria)
• M. François-Xavier PERRIN, Pr, University of Toulon (MAPIEM)

will defend her PhD thesis in Chemistry, on the topic:

on Wednesday December 14th, 2016 at 10:00 AM, at the University Ferhat Abbas Sétif 1 Algérie - El Bez - Cellule de Télé-Enseignement CTE ou salle de visio-conférence
and by videoconference at the University of Toulon, Bâtiment A (IUT) salle des Commissions

before a jury composed of :

• D. BENACHOUR, Professor, Université de Sétif 1, President
• N. CHELALI, Professor, Centre Universitaire de Bordj Bou Arréridj, Rapporteur
• T. DJENIZIAN, Professor, Aix-Marseille Université, Examiner
• F. LALLEMAND, Professor, Université de Franche-Comté, Rapporteur
• B. NESSARK, Professor, Université de Sétif 1, supervisor
• FX PERRIN, Professor, Université de Toulon, supervisor

Abstract:

In this study, we prepared two conductive composite materials based on polyaniline (PANI) by electrodeposition. First, we investigated the development of new polyaniline / LiMn₂O₄ composite films for application as cathode material in lithium-ion batteries. Analysis by X-ray diffraction, EDS analysis and FTIR spectroscopy confirmed the incorporation of LiMn₂O₄ in composite films. The electrochemical analysis of the films obtained showed a higher conductivity of the composite films compared to the conductivity of the films of PANI. The second part was devoted to the preparation of oxidized graphene (GO) from graphite by 2 methods of synthesis derived from the method of Hummers. The results showed that the degree of oxidation of the graphene sheets was not the only criterion in assessing the stability of GO in water. Electropolymerization of aniline in a neutral electrolyte containing GO sheets was carried out to prepare PANI-GO composite films. The neutral electrolytic medium leads to PANI oligomer chains of low molecular weight with a significant proportion of aromatic mono units and 1,2-di-substituted units in the final structure. The electrodeposition was performed on inert and oxidizable metals. The corrosion protection efficiency of PANI-GO composite films was studied in HCl corrosion medium.

Keywords: polyaniline, graphene, electropolymerization, Lithium ion batteries, Composite films.