Missions

lHigh-entropy materials (HEMs) are a rapidly evolving class of materials in the field of materials science, offering promising properties for applications such as catalysis, energy storage, and optoelectronics. However, their photoluminescence properties have been less thoroughly explored. In this context, the AI-Unclon project funded by the ANR aims to use machine learning tools to predict the evolution of photoluminescence colors in high-entropy materials based on compositional variations, thereby paving the way for innovative applications in LED-type lighting, thermometry, telecommunications, and anti-counterfeiting.
As a proof of concept, an AI-assisted synthesis method will be developed to produce luminescent materials for anti-counterfeiting and LED lighting applications. Phosphates and silicates synthesized at low temperatures will be co-doped with multiple activators, such as rare earth elements or transition metals, using a robotic platform (IMN Nantes). A subsequent heat treatment with a temperature gradient will be applied to modify the oxidation states of the dopants. The resulting materials will exhibit multiple excitation bands corresponding to each activator, enabling specific evolution of emission colors under different excitation wavelengths.
The photoluminescence properties will be characterized in high throughput using a robotic platform. Based on the collected data, machine learning will be employed to predict the emission color evolution as a function of excitation wavelength for all materials prior to synthesis. An automated search among millions of possible combinations of experimental parameters will be conducted to discover luminescent materials for anti-counterfeiting and LED lighting applications.

Activités

As part of this project, which will take place at IRCELYON, the focus will be on adapting synthesis protocols for phosphate matrices (such as apatite, rhabdophane, monazite, etc.), silicates (such as britholite), and others for their implementation on the Hiway-2-mat platform in Nantes. The targeted materials will be primarily synthesized in aqueous media under ambient air conditions, with specific doping using lanthanides or transition metals. All materials obtained will undergo thorough structural characterization at IRCELYON (X-ray powder diffraction, SEM, TEM, TGA, etc.). The characterization of optoelectronic properties will be carried out in collaboration with IMN.

Compétences

Good skills in solid state synthesis and colloidal synthesis
XRD diffraction analysis by single crystal and powder X-ray diffraction
Photoluminescence

Contexte de travail

IRCELYON is a joint research unit between the CNRS and the University of Lyon, which brings together the heterogeneous catalysis expertise of the Lyon region to create the largest catalysis laboratory in France and Europe. The laboratory comprises 80 permanent researchers from the CNRS and the University of Lyon, as well as a similar number of doctoral and postdoctoral students.

The scope of the position includes:
• A stimulating working environment with close contact with research staff
• An on-site restaurant offering affordable lunch options
• Partial reimbursement of transport tickets (75%) or a sustainable mobility package
• A site accessible by public transport + secure car/bicycle parking

Le poste se situe dans un secteur relevant de la protection du potentiel scientifique et technique (PPST), et nécessite donc, conformément à la réglementation, que votre arrivée soit autorisée par l'autorité compétente du MESR.

Contraintes et risques

No identified risks