Master and PhD positions

Design & Synthesis of Novel TADF Polymer for Opto-Electronic Application.

PhD Supervisors : Anthony D'Aléo (anthony.daleo@ipcms.unistra.fr ) and Nicolas Leclerc (leclercn@unistra.fr)

Laboratory : Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS) & Institut de Chimie et Procédé pour l'Energie, l'Environnement et la Santé (ICPEES)

Starting date : October 2023

Funding : HiFunMat Grant

Offer : pdf

Apply directly via CNRS Emploi

Organic Light Emitting Diodes (OLEDs) have reached the market by being introduced in our smartphones and TVs. To date, the dyes that are used in the emitting layer are composed of coordination complexes of iridium for instance. Since iridium is a noble metal that is rare and more and more expensive, a more viable alternative was found by using purely organic dyes. To match the performances of the iridium complexes, a mechanism called Thermally Activated Activated Delayed Fluorescence (TADF) involved in designed organic dyes has been developed and is optimized nowadays (without reaching commercialization yet). Following this concept, we have shown that curcuminoid borondifluoride (CurcBF2) as small molecules could be used in an OLED emitting layer showing efficient performances above 720 nm. The use of small CurcBF2 molecules blended in the host presents the disadvantage to form films that do not show morphological stability.

In this project, we aim at synthesizing and studying polymers containing CurcBF2 for applications in organic electronics. These polymers will present TADF properties allowing them to recycle triplet into singlet excited states. Such properties are indeed of interest and are expected to lead to a technological breakthrough in organic electronic applications. While TADF properties will be provided by the CurcBF2 moiety, the polymer structure will
allow controlling the aggregation of the dyes by choosing the quantity of the CurcBF2 entity relative to the other monomer. Such control is not possible to be achieved with small molecule in blend since CurcBF2 tends to form dimeric aggregates. This work will therefore permit to unravel the spin-orbit component of TADF mechanism. Our strategy also aims at improving the morphological stability which constitutes a prerequisite for industrial use.

We are looking for a highly motivated candidate with a chemistry background, good English communication skills, and the ability to work in a team. Knowledge in photophysics would be appreciated.

Catalytic localism in layer-by-layer composite films for light-driven water treatment

PhD Supervisors : Nicolas Keller (nkeller@unistra.fr ) and Olivier Felix (olivier.felix@ics-cnrs.unistra.fr)

Laboratory : Institut de Chimie et Procédé pour l'Energie, l'Environnement et la Santé (ICPEES) & Institut Charles Sadron (ICS)

Starting date : October 2023

Funding : HiFunMat Grant

Apply directly via CNRS Emploi

Water treatment is a priority worldwide health issue that scientists must address. In particular, in hospitals and the care sector, wastewater is polluted by medical products (antibiotics, anti-cancerous, anti-inflammatory or contraceptive drugs). Impact on the world's population health is dramatic at short- and long-term as treatments in place to date are not efficient enough, with eg. higher cancer risks and reduction of the human reproductive capacity. The development of novel sustainable cost-effective water treatment technologies is thus necessary.
In this context, H2O2-driven photo-CWPO catalysis is a high-prospect advanced oxidation process operating under solar light for mineralizing those refractory compounds in water at room-temperature. Albeit very active, and although H2O2 is a green oxidant, producing only H2O and O2 as end-products, this catalysis still faces a limited perspective for technological deployment, that results from the use of costly and non-sustainably produced H2O2 instead of O2 as oxidant.
The aim of the PhD thesis is thus to develop novel multi-functional catalysts for solar light-driven water treatment by applying an innovative strategy of catalytic (chemical) localism. By analogy to the local production and consumption of goods supported by the localism doctrine, this new concept is proposed to combine two catalysts working in synergy under solar-light, the first one producing H2O2 from molecular water and O2, and the second one using H2O2 for degrading the pollutants. To do so, we will rely on the bottom-up layer-by-layer self-assembly to precisely control the spatial positioning of both catalysts and the properties of the multilayer catalysts.
The project aims finally at validating the use of non-pathogenic bacterial biofilms as sentinel (sensor) of the water quality, by exploiting the capacity of biofilms to be affected by the presence of pollutants (especially antibiotics).

This multidisciplinary work at the frontier between chemistry, materials science, nanoscience, and microbiology will involve a wide span of research aspects:
- the synthesis, physico-chemical characterization and testing of solar light active heterogeneous catalysts in water treatment against antibiotic targets,
- the elaboration of films by layer-by-layer self-assembly and their advanced characterization,
- the study of the growth and characteristics of model biofilms.
The thesis is intended for a candidate (M/F) with a master degree in chemistry, physical chemistry, materials science or nanoscience, with a strong motivation in microbiology. Knowledge or first experience in microbiology or biochemistry will be an asset.
The candidate (M/F) will work in a dynamic, collaborative and international environment. Excellent communication skills (both written and oral) in English are expected (equivalent to level B2 according to the Common European Framework of Reference for Languages), while knowledge of French is not mandatory.

Development of elastomeric gaskets with barrier properties for cosmetic / pharmaceutical formulations

PhD Supervisor : Florence Bally-Le Gall (florence.bally-le-gall[at]uha.fr) & Karine Mougin (karine.mougin[at]uha.fr)

Laboratory : Institut de Science des Matériaux de Mulhouse (IS2M)

Starting date : October 2023

Funding : CIFRE Grant with Aptar

Offer : pdf

Aptar is a global leader in drug delivery, consumer product dispensing, and active material science solutions. We use insights, design, engineering, and science to create dosing, dispensing, and protective packaging technologies for the world’s leading brands – small marvels of sophisticated engineering and innovative design that make a meaningful difference in the lives, looks, health, and homes of millions of people around the world. We offer a full set of associated services to support customer speed-to-market.
On the Aptar Val De Reuil site, our main focus is to develop and manufacture gaskets used in our metering valves for pressurized metered dose inhalers, and multidose pumps, for perfumes, cosmetics, or nasal drug delivery.

The subject of this PhD project is to develop an elastomer-based gasket with barrier properties for cosmetic, perfumery, or pharmaceutical formulations used in dispensing devices without degrading their mechanical and elastic performance (properties compatible with assembly and final application).
The chemical resistance of the gaskets may be provided by the surface functionalization of the gasket and/or possibly by an improvement in the formulation of the latter. This study will aim to increase the gasket's impermeability with respect to molecules in contact (mainly present in liquid form). The innovative materials and surface treatments offered will be developed to meet customer and market needs and in compliance with the new REACH standards.

The main objectives of this PhD project are:

• to investigate the physico-chemical surface properties of chosen elastomers in contact with small organic molecules; particularly to understand the spatio-temporal diffusion of the product in the material.
• to functionalize the elastomer using either plasma treatment or self-assembly process to increase the barrier property of the seals.
• to investigate the mechanical performances of the treated (and not) elastomers sealing gaskets in contact (or not) with small organic molecules using a multiscale approach; the aim is to understand the critical parameters inducing aging of elastomers and its loss of mechanical properties during molecules delivery.
• to propose a binary system allowing improving the long-term stability of the gasket.

The candidate should have a background (Master or Engineer degree or equivalent) in material science, chemistry, and good skills in surface science. A strong interest in multidisciplinary approaches (material science, chemistry and physics), autonomy, and good experimental skills are highly recommended.

Functionalization of carbon monoliths with hierarchical porosity by plasma polymerization

PhD Supervisor : Julien Parmentier (julien.parmentier@uha.fr)

Laboratory : Institut de Science des Matériaux de Mulhouse (IS2M)

Starting date : October 2023

Funding : Grant of the UHA

Offer : pdf

Porous carbonaceous materials are present in many fields of application such as catalysis (catalyst support), water /gas depollution, gas storage / separation and energy storage. They have the advantage, with a relatively low cost, to be easily prepared from biosourced precursors and in monolithic form. To improve the performances of these bulk porous materials and to extend their field of application, a functionalization of their internal surface is often carried out but its control is made difficult by problems of diffusion of the reactive species in the tortuosity of the material. Plasma polymerization has rarely been investigated to functionalize such materials but could be a relevant process to achieve such a purpose while being compatible with an eco-design approach. It is supposed to lead to the deposition of a thin film of functional polymer (typically a few tens of nanometers thick). This green process, operating in gas phase, so without any solvent; enables a fast surface modification step and allows to bring very varied functional groups to the surface of the material (hydrophilic, hydrophobic groups...). However, the functionalization limitations of this process, in particular on the surface of porous and electrically conductive bulk carbonaceous materials, are still not known. Preliminary works have been carried out at the Institute of Materials Science of Mulhouse (IS2M) in collaboration between the Carbon and Hybrid Materials (CMH) axis and the Functional Polymers Engineering (IPF) axis, specialized in the field of porous carbons and plasma polymerization respectively. It has paved the way of the potentialities of this functionnalization technique applied to bulk carbon porous monoliths but in-depth studies are now needed to fully control and understand the plasma process within such materials.

Three scientific challenges will be addressed during this PhD work: i) the synthesis of porous carbon monoliths with controled porosities (size and organisation) and different degrees of graphitization, ii) the development of a methodology to assess the plasma polymerization mechanisms within porous and conductive bulk materials and, iii) the investigation of the potential applications of those functionalized materials based on adsoprtion/absorption phenomena.

Applicants should have a Master or Engineer degree (or equivalent) in a relevant chemistry or materials science discipline. Interest and enthusiasm for surface chemistry is essential while theoretical and experimental skills in materials synthesis, surface functionalization and characterization will be an advantage. The applicants should show initiative and seriousness to work in team. They should have good organization and communication skills.

We aim at synthesizing and studying polymers containing curcuminoid borondifluoride (CurcBF2) for applications in organic electronics. These polymers will present thermally activated delayed fluorescence (TADF) properties allowing to recycle triplet into singlet excited states. Such properties are not common and are expected to lead to a technological breakthrough in organic laser diode application.
While TADF properties will be provided by the CurcBF2 moiety, the polymer structure will allow to control the aggregation of the dyes by choosing the quantity of the CurcBF2 entity relative to the other monomer. Such control is not possible to be achieved with small molecule in blend since CurcBF2 tend to form dimeric aggregates. This work will therefore permit to unravel the spin-orbit component of TADF mechanism. Our strategy also aims at improving the morphological stability which constitutes a prerequisite for industrial use.

Water treatment is a priority health issue that scientists must address, as treatments in place to date fail to flush a wide span of high-concern biorecalcitrant organic pollutants, antibiotics in particular. Among high-prospect AOPs, H2O2-driven photo-CWPO catalysis can yield full mineralization of refractory compounds in water at high reaction rates under solar light. However, it still faces a limited perspective for technological deployment due to the necessary external use of costly, non-sustainable H2O2 as oxidant. Based on the concept of catalytic localism, we aim at designing catalytic architectures that embark solar light active catalysts allowing in-situ H2O2 synthesis from H2O and O2 and further usage. They will be built by layer-by layer self-assembly to control the spatial positioning of both catalysts, using organic and inorganic polyelectrolytes. We finally aim at validating their use on non-pathogenic multi-species bacterial biofilms used as sentinels of water quality.

STED-like Multiphoton Lithography using Bi-functional Self-Immolative Monomers

Project acronym : UNIVERSTED

PhD Supervisors : Dr HDR Jean-Pierre Malval / Dr Hélène CHaumeil

PhD student : Aissa Id Boualim

Laboratory : Institut de Science des Matériaux de Mulhouse (IS2M), Mulhouse / Laboratoire d'Innovation Moléculaire et Applications, Mulhouse

Starting date : October 2022

Research team's webpage

Summary:

Metamaterials are nanostructures with subwavelength dimensions that allow light to be controlled in unprecedented ways. These materials can be prepared by self-assembly of nanoparticles, and the resulting optical properties depend not only on those of the individual building blocks, but mainly on interactions between them. The challenge is thus to measure light interaction with the nanostructures at the micro/nano scale in order to tune the macroscopic far-field response.
The SUPERCLASS project consists in investigating the optical properties of oriented silver nanowire films as function of light polarization and sample deformation. Polarization-dependent 2D Spectral maps will first be measured using white light interference microscopy. Then, super-resolved local spectroscopy using a microsphere will be developed to improve the lateral spatial resolution below the micrometre scale. This experimental data will be compared to rigorous electromagnetic simulations to obtain a better understanding at various scales.

The main objective of the Hydro-NHC project is to develop solutions that can simultaneously eradicate cancer cells and cancer stem cells (CSC) from glioblastoma, by applying localized treatment. To address this issue and on the basis of our previous results and hypotheses, we propose to develop organometallic complexes of type metallo-carbene -based on platinum- which induce mitochondria-dependent apoptosis in malignant cells. These complexes will then be formulated and integrated into biocompatible hydrogels based on albumin or hyaluronic acid, allowing prolonged local administration of the therapeutic agent in the heart of the malignant tissue, avoiding the need to cross the blood-brain barrier (BBB).

Supported catalysts are the major class of catalysts used in industry. With the advent of eco-efficient photoredox catalysis processes, there is a need for a new set of photocatalyst supports. PhotoCat project aims at preparing a new generation of precisely shaped porous polymer supports embedding non-toxic organic dyes. This project combines the competences of IS2M in photopolymerization and LIMA in heterogeneous photocatalysis. To ease synthesis, a photocatalyzed radical polymerization is carried out, thus avoiding the need for an initiator and resulting in the single-step preparation of the support and the physical trapping of the photocatalyst. Precise shaping of the support in the form of monoliths or particles are made possible by 3D printing and emulsion polymerization techniques. Control of porosity from micro- to macro scale is ensured by external porogens via templating or phase separation effect. These new heterogeneous photocatalysts are evaluated for model organic transformations (Aza-Henry reaction, [2+2] cyclization of dienone, 1O2photosensitization-oxidation) in batch and flow photoreactors