Intitulé de l'offre : PhD (H/F): NEW GREEN CARBON FIBRES MADE FROM LIGNIN; IN-SITU STUDY OF THEIR GRAPHITIZATION BY X-RAY SCATTERING
Référence : UMR8502-PASLAU-006
Nombre de Postes : 1
Lieu de travail : ORSAY
Date de publication : lundi 4 septembre 2023
Type de contrat : CDD Doctorant/Contrat doctoral
Durée du contrat : 36 mois
Date de début de la thèse : 1 novembre 2023
Quotité de travail : Temps complet
Rémunération : 2 135,00 € gross monthly
Section(s) CN : Condensed matter: organisations and dynamics
Description du sujet de thèse
Carbon fibres are widely used, including to reduce weight, improve fuel efficiency and increase vehicle range. Although they contribute to sustainability during their use, they are manufactured from petrochemicals through an energy intensive carbonization process. This thesis topic is part of a project co-funded by CNRS in France and Imperial College in London, UK, to develop a new class of "green" carbon fibres from lignin (a renewable precursor derived from wood) using less energy for the conversion.
Two PhD students will be involved in the project, one at the Laboratoire de Physique des Solides (CNRS/Université Paris-Saclay) and the other at Imperial College. The project involves the exchange of data and samples, and the progress of each PhD student will be accelerated by the contributions of the other. The PhD student at Imperial College will be responsible for the production of hybrid lignin/carbon nanotube or polymer (polyvinyl alcohol) fibres by spinning, studying their mechanical and electrical properties, and optimizing the production process.
The subject of the PhD student at the Orsay Solid State Physics Laboratory is detailed below.
It concerns a key element to obtain quality fibres: the understanding and control of the carbonization and graphitization process of lignin during the heating of fibres. The subject of this thesis is the study in-situ by X-ray scattering, in the laboratory or on synchrotron, of the evolution of the structure and texture of precursor fibres during their transformation. The graphiticity of the product is critical to its performance, and will be related both to the lignin chemistry and the presence of the carbon nanotubes or polymer additives. The PhD student will use new environmental cells for his/her experiments allowing tensile and temperature studies to be performed in situ. X-ray scattering experiments will be performed at large angles, to analyse structural aspects, but also at small angles, to evaluate the shape and orientation of (nano)pores in the fibre. The PhD student will also participate in the development of the formalism and codes necessary to analyse both the amorphous and crystalline phases present, including the evolution of their proportions, domain sizes, and orientations [1,2,3,4]. The CNRS PhD student will travel to London (at least three months in total) to understand the manufacturing process of the fibres and to perform complementary analyses (e.g. Raman scattering, confocal/electron microscopy).
Contexte de travail
Experimental work and modeling.
Profile of the PhD student:
- Strong background in solid state physics or materials
- Enthusiasm for both practical experiment and formalism development
- Excellent organizational and communication skills
- Existing programming skills (e.g. Python) will be appreciated