David Lacroix

This PhD position at Université de Lorraine focuses on photothermal investigations of thermal transport in phase-change nanocomposites for energy storage systems. The project addresses a critical challenge in thermal energy storage (TES): the low thermal conductivity of phase-change materials (PCMs), which limits the efficiency of heat-charging and discharging in storage devices. By embedding PCMs within nanostructured solid matrices, such as porous silicon, the research aims to enhance effective thermal properties and understand the complex thermal transport behavior, especially near the phase-change temperature. The main objective is to develop and apply advanced non-contact photothermal and photoacoustic techniques for quantitative characterization of thermal transport in PCM-based nanocomposites. The focus is on the solid–liquid phase-transition regime, extracting effective thermal diffusivity and conductivity, and establishing correlations between confinement effects, phase-change behavior, and macroscopic thermal performance. Model systems will use porous silicon matrices infiltrated with n-alkane PCMs (e.g., hexadecane), and phase-change properties will be studied using Differential Scanning Calorimetry (DSC) and Raman spectroscopy to probe local structural and phase evolution under confinement. The PhD student will join LEMTA (Laboratoire Énergies & Mécanique Théorique et Appliquée, UMR 7563), a joint research unit of Université de Lorraine and CNRS, and become part of the TEMIN (Thermal Engineering at Micro- and Nano-scales) team. Supervision will be provided by Prof. David Lacroix and Dr. Mykola Isaiev. LEMTA offers a unique experimental environment with access to photothermal and photoacoustic techniques, Raman thermometry, infrared thermography, thermoreflectance methods, and scanning thermal microscopy. The project is embedded in a strong international collaboration with Taras Shevchenko National University of Kyiv, enabling complementary atomistic simulations of thermal transport in confined PCMs. Applicants should have a Master’s degree (or equivalent) in physics, materials science, thermal engineering, or a closely related field. Essential skills include knowledge of heat transfer and thermal transport properties, experimental experience or strong interest in thermal characterization techniques, proficiency in data analysis and modeling using Python and/or MATLAB, and basic knowledge of optics and electronics relevant to experimental setups. Experience with photothermal or photoacoustic techniques, phase-change materials, and non-contact thermal measurements (Raman, IR, thermoreflectance) is highly desirable. To apply, candidates should submit their application via the academic positions portal, including a CV, cover letter, and supporting documents. For further information, applicants may contact Prof. David Lacroix or Dr. Mykola Isaiev. The position offers a stimulating research environment, access to state-of-the-art facilities, and opportunities for international collaboration in the field of thermal energy storage and nanocomposite materials.