Deposition of Mixed Oxide Nanostrucrured Coatings by Solution Precursor Plasma Spray for Disinfection

IRCER, a scientific research center

Located in Limoges, Nouvelle Aquitaine, the birthplace of the ceramics industry in France, the scientific research center now bridges tradition and modernity by innovating in the development of high-tech ceramics that meet new industrial and societal challenges (energy, information and communication technology, health, eco-materials, etc.). The IRCER brings together all of its staff (200 members) and equipment in a single 8,500 m² building called the “European Ceramics Center.”

Internationally recognized, the institute brings together teams of CNRS researchers and faculty members from the University of Limoges in the fields of chemistry, physics, and mechanics of ceramic-based materials, and plasma process physics, as well as engineers, technicians, and administrative staff (ITA/BIATSS).

Supervisor:

1 : Alan Kéromnès, Professor

2 : Mathieu Tartarin, PhD Student

3: Vincent Rat CNRS senior researcher

Context and objective of the study: 

Water treatment technologies that use sustainable, less energy-intensive processes with reduced use of chemicals, such as photocatalysis, are becoming crucial due to global warming. To address these challenges, the ANR PASSION project, of which this internship is a part, aims to produce nanostructured mixed oxide coatings using Solution Precursor Plasma Spraying (SPPS) for disinfection by means of photocatalysis.
SPPS process belongs to the thermal spraying family wherein raw materials, like ceramic powders, suspensions or solution precursors, are injected within a high enthalpy and momentum source to be sprayed onto a prepared substrate to form a coating. SPPS has been extensively studied for protective coating applications such thermal barrier coatings for high pressure turbines. When the precursor solution is injected into the plasma jet as liquid stream, liquid primary fragmentation takes place resulting in droplets. Solvent is subsequently evaporated resulting in precipitation of a precursor solute which is then pyrolyzed and sintered, before being melt [1]. Recently, it was shown that mono-oriented ZnO coating for photocatalysis application can be obtained as a thin film on polycrystalline alumina and sapphire single crystals. Coating analysis has suggested a crystal synthesis directly upon the substrate opening up a new synthesis route by means of SPPS [2].
The objective of the internship is to produce nanostructured heterogeneous junction coatings of mixed oxides such as ZnO/CuO or ZnO/SnO2 while establishing and optimizing the relationships between the operating parameters and the coatings properties. Following this study, the photocatalytic properties of the coatings obtained will be investigated. This study will focus in particular on the ability of the materials to degrade organic pollutants such as methylene blue using a lamp emitting at 380 nm (UV), for example, but also on the electrochemical study of reactions by linear and cyclic voltammetry, polarization curves, and electrochemical impedance measurements at the electrolyte-electrode interface in order to determine the effectiveness of coatings and their service life.
[1] M. Gell, E.H. Jordan, M. Teicholz, B.M. Cetegen, N.P. Padture, L. Xie, D. Chen, X. Ma, J. Roth, Thermal Barrier Coatings Made by the Solution Precursor Plasma Spray Process, J. Therm. Spray Technol. 17 (2008) 124–135. https://doi.org/10.1007/s11666-007-9141-5.
[2] M. Tartarin, P. Duport, G. Rivaud, L. Youssef, S. Goutier, V. Rat, P. André, A. Kéromnès, Oriented ZnO nanostructured coatings deposited by Solution Precursor Plasma Spraying, Surfaces and Interfaces 72 (2025) 107355. https://doi.org/10.1016/j.surfin.2025.107355

We are looking for a student in their second year of a master's degree or in their final year of engineering school (in materials science). The candidate must be familiar with semiconductors, photocatalysis, and electrochemistry or plasma projection. We are looking for a motivated, rigorous person who is able to work in a team and is autonomous.