- Thermoelectric materials
- Electronic and thermal transport
My research activity is devoted to the development and study of the thermoelectric properties of bulk and nanostructured bulk intermetallics. These materials can convert a thermal gradient into electrical voltage (Seebeck effect) or convert an electrical current into heat flow (Peltier effect). The thermoelectric figure of merit (ZT) of these materials directly determines the performance of the thermoelectric generators or refrigerators they constitute.
I pursue several goals, both fundamental and applied. Thus, my colleague C. Barreteau and I are looking for new thermoelectric materials by a numerical screening that she carries out in a well-chosen set of chemical compositions. I am also studying the effect of the nanostructuring of these materials (nanoprecipitates or nanograins) on their electronic and thermal transport properties. This leads to an improvement in their thermoelectric properties and thus to bring them closer to energy conversion applications.
I am the scientific coordinator of the ANR project “LoCoThermH” (Low Cost Thermoelectric Heusler alloys 2018 – 2022), which aims to improve the thermoelectric properties of the Heusler Fe2VAl alloy. The other partner in the project is the Charles Gerhardt Institute (ICG, Montpellier) which, under the direction of P. Jund, performs “first principle” calculations of electronic and thermoelectric properties to guide the experiments for which we are responsible. In this context, I am supervising the thesis of A. Diack-Rasselio, doctoral student at the University of Paris-Est Créteil, funded by this project.
I am also conducting research on the nanostructuring of n-type skutterudites (CoSb3, Co0.94Ni0.06Sb3 or AyCo4Sb12 A = In, Yb, y ~ 0.2). I was a pioneer in the use of grain growth inhibitors to obtain materials that are highly densified by sintering (99%) and display skutterudite grains smaller than 150 nm. In this way, the thermal conductivity is greatly decreased, and the figure of merit is significantly improved. For example, the figure of merit increases from ZT = 1.1 to ZT = 1.4 in nanograined In0.2Co4Sb12.
TEACHING AND TUTORING
I teach a course on “Thermoelectric Materials” in Master 2 “Materials Science and Engineering”, course “Advanced Materials and Nanomaterials”, at the University of Paris-Est Créteil (6 hrs / year).
I am responsible for the “Metallurgy and Inorganic Materials (M2I)” department, one of the two scientific departments that structure the ICMPE. This department is made up of 46 permanent researchers, (associate) professors and technicians and 40 PhD students, post-docs, interns. Its recurring credits are managed by a department council that I chair (CDD-M2I).
I am chairman of the scientific board of the “Thermoelectricity” Scientific Interest Group.