Séminaire interne au LMGP - 16/11/2018 - Pr. Marie-Ingrid Richard

Coherent X-ray diffraction for a look inside nanostructures
Associate Pr. Marie-Ingrid Richard
IM2NP, Aix-Marseille University, ESRF

Characterising the structural properties (strain gradients, chemical composition, crystal orientation and defects) inside nanostructures is a grand challenge in materials science. Bragg coherent diffraction imaging (Bragg CDI) can be utilized to address this challenge for crystalline nanostructures. A resolution of the structural properties of less than 10 nm is achieved up-to-date [1]. As an example, the Bragg CDI technique allows understanding the interplay between shape, size, strain, faceting [2], composition and defects at the nanoscale. I will demonstrate that Bragg CDI on a single particle model catalyst makes it possible to map its local strain/defect field and directly images strain build-up close to the facets. The localised strain modifies sorption energies of the reactants. In situ [3] and operando Bragg CDI was also performed: it was possible to track a single particle in liquid and gas phase environments, to monitor its facet changes and to measure its strain response to gas or electrochemical reaction.
This technique opens pathways to determine and control the internal structure of nanoparticles to tune and optimise them during chemical reaction or growth.
[1] S. Labat, M.-I. Richard, M. Dupraz, M. Gailhanou, G. Beutier, M. Verdier, F. Mastropietro, T. W. Cornelius, T. U. Schülli, J. Eymery, and O. Thomas, ACS Nano 9, 9210 (2015).
[2] M.-I. Richard, S. Fernandez, J. Eymery, J.-P. Hofmann, L. Gao, J. Carnis, S. Labat, V. Favre-Nicolin, E. J. M. Hensen, O. Thomas, T. Schülli, and S. J. Leake, Nanoscale 10, 4833 (2017).
[3] M.-I. Richard, S. Fernández, J. P. Hofmann, L. Gao, G. A. Chahine, S. J. Leake, H. Djazouli, Y. De Bortoli, L. Petit, P. Boesecke, S. Labat, E. J. M. Hensen, O. Thomas, and T. Schülli, Rev. Sci. Instrum. 88, 093902 (2017).

Financial support to this work by ANR JCJC and t-ERC Charline (ANR-16-CE07-0028-01 and
ANR-18-ERC1-0010-01) is gratefully acknowledged.

Infos date
Grenoble INP - Phelma
3 parvis Louis Néel - 38000 Grenoble
Accès : TRAM B arrêt Cité internationale
Infos lieu
14h salle de séminaire du LMGP