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Senior Research Engineer (CNRS)
I. By the way
2004-present: CNRS Research Engineer
HDR Chemical Sciences, University of Paris Sud (Orsay Center), defended on February 18, 2004.
1994-2004: CEA engineer at the Léon Brillouin Laboratory (Saclay), responsible for a neutron diffractometer
PhD in Materials Sciences, University of Reims and Léon Brillouin Laboratory (CEA Saclay), defended on September 18, 1993.
Degree in Nuclear Engineering, specialization in Physics of Materials, Politecnico of Milan (Italy) obtained on October 24, 1989.
Teachings & Responsibilities
Part to be completed by the scientist
Ii. Research activities
Growth of high-quality strontium-doped (Nd,Pr)-nickelate single crystals
Large and high-quality single crystals of Nd(2-x)SrxNiO(4+δ) and Pr(2-x)SrxNiO(4+δ) (x=0, 0.1 and 0.5) were developed by the floating zone technique using an image furnace. These single crystals were characterized by neutron and X-ray diffraction as well as electron microscopy, revealing their excellent quality in terms of composition, homogeneity and crystal quality. For each crystal, the oxygen content was determined by thermogravimetric analysis in a reducing atmosphere. Transmission electron microscopy revealed an immeasurable complex structure for (Pr/Nd)2NiO4.25 with a 2D modulation vector linked to the order of oxygen.
My main activity within the "Oxide Materials" group of the Chemistry of Materials, Nanostructures and Materials for Energy Department (Department D4) of the ICGM, is crystallogenesis, and more particularly the growth of large single crystals of oxides by image furnace (molten zone method), and their characterization by diffraction of X-rays (synchrotron and laboratory) and neutrons. My expertise is the combination of crystal growth techniques and advanced structural characterization techniques combined with sophisticated and unconventional analysis methods, such as "Maximum Entropy Method", with a large part of large instruments (nuclear reactor and synchrotron). In particular, our interest has focused onK2NiF4 structures, potential candidates for fuel cells, and also on oxygen-deficient perovskites. Here, when oxygen doping is performed via topotactic reaction mechanisms at low temperatures, it results in structural and electronic complexity related to simultaneous charge order and spin effects that can interact, leading to very complex phase diagrams.
Collaborations & Contracts
- 2020-2024: ANR-DFG PRCI, "ExODiff: Exploring oxygen diffusion mechanisms in Pr2NiO4+d under in situ conditions by neutron scattering: interplay between structure and lattice dynamics", coordinator
- 2020-2024: ANR PRCE, "DESCARTES: Impact of micro- and defect structure on the catalytic performance of alternative support materials"
- 2015-2019: ANR PRCE "CaFeCat: CaFeO5 analogous Brownmillerites prospecting replacement of ceria-based materials for heterogeneous catalysis", (task "structural and microstructural characterization")
- 2014-2019: ANR-SNF, PRCI, "SECTOR: Structural induced Electronic Complexity Controlled by low Temperature Topotactic Reactions", (head of the "crystal growth" task)
- 2014-2018: ANR PRC "AMOXIS: Assisted Mechanisms for Oxygen Ionic Conduction in non-stoichiometric Oxides" (head of the "crystal growth and structural characterization" task)
Iii. Scientific production