A PhD opportunity to work on imogolite nanotubes between the Laboratoire de Physique des solides and Laue-Langevin Institute.

The Laboratoire de Physique des Solides (LPS) is a joint research unit of the Université Paris-Sud and the CNRS: the UMR 8502. It mainly depends on the CNRS Institute of Physics, and on the 28th section of the National Council of Universities. It gathers about a hundred researchers, experimentalists and theorists, and welcomes many students and visitors (more than sixty). Our research activity is supported by about 60 engineers, technicians and administrators.

The Institut Laue-Langevin is an international research centre at the leading edge of neutron science and technology. As the world’s flagship centre for neutron science, the ILL provides scientists with a very high flux of neutrons feeding some 40 state-of-the-art instruments, which are constantly being developed and upgraded.

Project:

Imogolite nanotubes (INT) are natural clay nanotubes SiAl2O7H4, capable of absorbing a large quantity of water, which could impact soil stability. In recent years, synthetic geo-inspired INTs GeAl2O7-xCxH4+2x, where the hydro-philicity of the inner wall is controlled by substituting internal hydroxyl groups by methyl ones, have been produced.
These geo-inspired nanotubes are model systems for studying new phenomena associated with water dynamics in nanoconfinement. The objective of the thesis is to understand the role of geometric confinement and surface chemistry on the adsorption and diffusion properties of water molecules. Water filling will be studied thanks to in-situ X-ray scattering experiments in a dedicated humidity chamber at LPS, while quasi-elastic neutron scattering and neutron spin echo experiments will provide access to diffusion within time scales from picoseconds to hundred of nanoseconds. In addition to the experiments, the PhD student will carry out molecular dynamics simulations, made possible by the determination of the structure of INTs in 2018 (figure above), in order to analyze the processes of water adsorption and diffusion at different time scales. External collaborations will allow him/her to put the results in perspective with thermodynamics insights from adsorption isotherms and with complementary diffusion experiments (NMR dispersion experiments performed at laboratoire PHENIX in Paris). The ambitious objective of the thesis is to obtain a consistent set of experimental and simulation data about the multiscale dynamics of water confined in model hydrophilic or hydrophobic nanoporous media and to present a global picture of the associated phenomena.

Candidate and supervision:

The ILL in Grenoble and the LPS in Orsay jointly advertise a 3-year PhD position in France, of which about the first 12 months will be spent in Orsay and the subsequent 24 months in Grenoble, both with regular visits to the complementary place. The thesis will be defended at Paris-Saclay University. The PhD project builds on a well-established collaboration between the supervisors who have co-supervised PhD students with publications in high rank journals. Two of them have been awarded by the Société Française de Neutronique in 2013 and by the Association Française de Cristallographie in Physics, in 2014. The candidate must have a broad knowledge of physics and he/she should be highly motivated by both experimentation and numerical simulations. He/she should possess organizational skills as well as the ability to work both independently and as part of a team.

How to apply:

Please send a cover letter, a detailed CV including academic records, and the names and contacts of two referees to the supervisors.

For more informations, download the document below.