Clusters and Reactivity

Leader: Claude Henry

Introduction

The research activity of the team is focused on the link between structure and reactivity of mono- and bimetallic supported clusters with the aim to bridge the “material” and “pressure” gaps in heterogeneous catalysis.

Two types of clusters are studied.

  • The first ones (from few atoms to 4 nm) are synthesized by UHV deposition of metal atoms on nanostructured ultrathin alumina films (0.5nm thick) obtained by high temperature oxidation of a Ni3Al (111) surface. By this method, hexagonal arrays of clusters having a sharp size dispersion (Dn/n=1/√n, n being number of atoms in the cluster). In the case of bimetallic clusters the chemical composition is tunable in the full size range. The clusters are characterized in situ by STM, XPS, GISAXS and GIXD.
  • Clusters from the second type (2 to 10 nm) are synthesized by chemical methods in liquid phase by reduction of metallic complexes in presence of surfactants. The size dispersion is low (10%), the morphology can be controlled. The bimetallic clusters are homogenous or of core-shell type. The cluster growth in solution is studied in situ by TEM by using a liquid cell in graphene or in silicon nitride. Their atomic structure is studied by HRTEM.
Agrégats
Hexagonal lattice of 35±6 Pd atoms clusters – Variation of CO adsorption energy as a function of the size of Pd clusters, showing the transition between molecular to bulk behavior – Variation of the reactivity towards CO oxidation of core-shell Pf-Pt nanoalloys; a maximum of reactivity is found for one ML of Pt on 10 nm Pd cubes.
The reactivity of the clusters as a function of their size, their morphology and their chemical composition is studied by gas adsorption (CO, O2, H2, NO…) and by bimolecular catalytic reactions (CO+O2, CO+NO….) at various pressures from UHV to atmospheric pressure.

From UHV (10-10 mbar) to 10-6 mbar the reactivity is studied in situ by a pulsed molecular beam technique (MBRS).

In the middle range pressure (10-6 to 10 mbar) mass spectrometry and AP-XPS (at synchrotron facilities) are used. At high pressure (10 mbar to 1bar) gas chromatography and direct (LSPR) or indirect nanoplasmonic sensing are used.

Agrégats 1
Growth of Pd-Pt nanoalloys observed in situ by HRTEM with a graphene liquid cell.

Publications

2024

Plasmonic sensing: FDTD calculations to interpret experimental LSPR water adsorption isotherms

Benjamin Demirdjian, Igor Ozerov, Frédéric Bedu, Alain Ranguis, Claude R Henry

Chemical Physics Letters 837:141063 (2024)10.1016/j.cplett.2023.141063

2023

Diffusive Dynamics of Bacterial Proteome as a Proxy of Cell Death

Daniele Di Bari, Stepan Timr, Marianne Guiral, Marie-Thérèse Giudici-Orticoni, Tilo Seydel, Christian Beck, Caterina Petrillo, Philippe Derreumaux, Simone Melchionna, Fabio Sterpone, Judith Peters, Alessandro Paciaroni

ACS Central Science (2023)10.1021/acscentsci.2c01078

Optimized OPEP Force Field for Simulation of Crowded Protein Solutions

Stepan Timr, Simone Melchionna, Philippe Derreumaux, Fabio Sterpone

Journal of Physical Chemistry B 127:3616-3623 (2023)10.1021/acs.jpcb.3c00253

2021

CO and O2 Adsorption and CO Oxidation on Pt Nanoparticles by Indirect Nanoplasmonic Sensing

Benjamin Demirdjian, Igor Ozerov, Frédéric Bedu, Alain Ranguis, Claude R Henry

ACS Omega 6:13398-13405 (2021)10.1021/acsomega.1c01487

Sequestration of Proteins in Stress Granules Relies on the In-Cell but Not the In Vitro Folding Stability

Nirnay Samanta, Sara Ribeiro, Mailin Becker, Emeline Laborie, Roland Pollak, Stepan Timr, Fabio Sterpone, Simon Ebbinghaus

Journal of the American Chemical Society 143:19909-19918 (2021)10.1021/jacs.1c09589

2019

Molecular Beam Study of the CO Adsorption on a Regular Array of PdAu Clusters on Alumina

Georges Sitja, Claude R Henry

Journal of Physical Chemistry C 123:7961-7967 (2019)10.1021/acs.jpcc.8b07350

Regular Arrays of Pt Clusters on Alumina: A New Superstructure on Al 2 O 3 /Ni 3 Al(111)

Georges Sitja, Aude Bailly, Maurizio de Santis, Vasile Heresanu, Claude R Henry

Journal of Physical Chemistry C 123:24487-24494 (2019)10.1021/acs.jpcc.9b05109

2018

Nonisotropic Self-Assembly of Nanoparticles: From Compact Packing to Functional Aggregates

Xavier Bouju, Etienne Duguet, Fabienne Gauffre, Claude R Henry, Myrtil L Kahn, Patrice Mélinon, Serge Ravaine

Advanced Materials 30:1706558 (2018)10.1002/adma.201706558

Water adsorption by a sensitive calibrated gold plasmonic nanosensor

Benjamin Demirdjian, Frédéric Bedu, Alain Ranguis, Igor Ozerov, Claude Henry

Langmuir 34:5381-5385 (2018)10.1021/acs.langmuir.8b00040

2017

Influence of Palladium on the Ordering, Final Size, and Composition of Pd-Au Nanoparticle Arrays

Aude Bailly, Georges Sitja, Marie-Claire Saint-Lager, Séverine Le Moal, Frédéric Leroy, Maurizio de Santis, Claude R. Henry, Odile Robach

Journal of Physical Chemistry C 121:25864-25874 (2017)10.1021/acs.jpcc.7b08254

CO Chemisorption on Ultrathin MgO-Supported Palladium Nanoparticles

Aimeric Ouvrard, Ahmed Ghalgaoui, Carine Michel, Clemens Barth, Jijin Wang, Serge Carrez, Wanquan Zheng, Claude R. Henry, Bernard Bourguignon

Journal of Physical Chemistry C 121:5551-5564 (2017)10.1021/acs.jpcc.6b10595

2016

Core-shell Pd-Pt nanocubes for the CO oxidation

Astrid de Clercq, Olivier Margeat, Georges Sitja, Claude R. Henry, Suzanne Giorgio

Journal of Catalysis 336:33-40 (2016)10.1016/j.jcat.2016.01.005

Charging C-60 islands with the AFM tip

Brice Hoff, Claude R. Henry, Clemens Barth

Nanoscale 8:411-419 (2016)10.1039/c5nr04541j

Collaborations

CINAM

  • C. Barth
  • B. Demirdjian
  • M. Gingras
  • F. Leroy
  • O. Margeat
  • C. Mottet
  • L. Peng

 

National

  • Institut Néel (Grenoble)
  • ISMO (Orsay)
  • LRS (Paris)
  • MONARIS (Orsay)         

 

International

  • H.J. Freund, FHI-MPG (Berlin) 
  • U. Heiz, TUM (Munich)