04/06/2019 Offres d'emploi

Offre de thèse/ PhD Proposal - Institut Pascal/ Lab Hubert Curien - 2019

Thesis on Development of optical microsensors based on surface plasmon resonance for oxidizing pollutant monitoring

Starting date: 01/10/2019

Context & objectives: (all informations inside the pdf)

Context: Air pollution is the first environmental cause of mortality with 3.7 million deaths due to outdoor exposures and 4.3 million deaths due to indoor exposures [1]. European and American epidemiological studies [2-4] have clearly established the link between the morbidity rate and the exposure to air pollutant concentrations commonly measurable in large urban areas. In Europe, the emission level of the main pollutants (nitrogen oxide NOx, ozone O3, volatile organic compounds VOCs, and fine particles PM) remains stable in most of the large cities [5]. Beyond the environmental consequences, monitoring air pollution is thus a real issue of public health [6]. Besides, if the health troubles caused by local and high level pollutant emissions are well identified, the risks induced by continuous exposure to small concentrations are poorly characterized because of their difficult assessment. The long-term impact of low concentrations below the exposure limits can only be determined by precise continuous measurements. Suitable low threshold and high resolution gas microsensors has therefore become a requirement.

Objectives: The project ANR-18-CE04-0008 - CAPTAIN « Optical sensors for the monitoring of air quality (NO2, O3 pollutants) is focused on the development of a new generation of optical sensors dedicated to the monitoring of gaseous pollutants for the control of outdoor and indoor pollution level. The quantification of very low concentrations of NO2 and ozone O3, with a high degree of selectivity and repeatability, represents the scientific lock we aim to overcome. The elaboration of microsensors highly sensitive to the targeted pollutants, robust, miniature, low cost, with low-power consumption represents the technical challenge that we want to address.

Scientific strategy:
Microsensors developed in the context of this project are based on optical transduction and exploit the grating excitation of surface plasmons, which have widely demonstrated their detection potential in chemical, biologic and gas sensing applications [7]. The selectivity is performed by functional sensitive nanolayers deposited onto the microstructured optical transducers. Materials are selected because of their preferential interactions with each targeted pollutant as well as their ability to be layered by means of simple technologies to be easily transferrable to the industrial project partners.
During this PhD, a novel variant of SPR-Surface Plasmon Resonance - based optical detection will be exploited. The patent protected innovative approach [25] proposed uses a coupled plasmon wave, but it exploits a novel switching effect between two reflected free space diffraction orders (0th and -1st orders) under the effect of the grating coupling of the incident wave to the plasmon mode [8, 9]. The measurement procedure consists in measuring the power of both propagating orders upon the variation of the measurand under fixed wavelength and incidence angle. The relative power variation measured optoelectronically is an analogic signal of the measurand variation which is the refractive index of the selective nanolayer under the presence of a pollutant.

Industrial partnership & exploitation
The microstructured surface of the optical transducers will be designed in cooperation with the industrial partner, SILSEF. Thanks to the technologies mastered, the technological feasibility of the optical transducers on flexible and rigid substrates will readily be studied. The skills of SILSEF in nanopatterning and surface functionalization will be advantageously used to optimize the compatibility between the transducers and the selective functional layers. SILSEF will then evaluate the conditions for large scale manufacturing.
While the tests in artificially polluted atmospheres will be firstly achieved by the academic partners, the measurements in more complex atmospheres and tests under real conditions will be planned using the measurements station of the second industrial partner, ENVEA. ENVEA will validate the obtained results and define the metrological performances to improve. At the end, ENVEA will evaluate the industrial exploitation of the microsensors in conformity with the existing directives for the completion of their existing product line Cairpol (french start-up created in 2006 and acquired by ENVEA in 2010).

PhD topic:
The missions of the PhD are multidisciplinary:
- Elaboration and optical characterizations of metallic and functional material nanolayers;
- Elaboration of the experimental platform of optical characterization under pollutants (opto-electronic instrumentation;
- Quantification of metrological performances of sensing devices: sensitivity, stability, response time, detection threshold, repeatability…
- Influence of interfering analytes and relative humidity on sensor responses;
- Intercomparison of sensor responses, modelling of gas/material/transducer interactions, performances optimization;
This doctoral position is strategic to reinforce the collaborative work and to initiate synergies between each partner into the consortium.

Profile of applicant:
The candidate must have a Master 2 or an engineering degree in Physics/Optics (Plasmonic, Nanophotonics) or Material Science obtained with excellent marks/rank.
The applicant must also have skills in instrumentation, LabVIEW development and basic knowledge about sensors. Because this project include academic and industrial partners, communication, listening skills as well as good English level will be highly appreciated.
Application form:
Please send cover letter + CV + summary of the master thesis (or topic) + master marks to: jerome.brunet@uca.fr and yves.jourlin@univ-st-etienne.fr

Reference
1. Prüss-Ustün et al, OMS report, (2016)
2. Anderson et al, Zent. Hyg Umwelt. 202(6) (1999)
3. Künzli et al, The Lancet 356, 795-801 (2000)
4. Popeet al, Jama 287 1132-1141 (2002)
5. Institut de Veille Sanitaire Bulletin BEH (2013)
6. Direction Générale de la Santé, Rapport (2016)
7. Homola, Chem. Rev. 108 (2), (2008)
8. O. Parriaux, Y. Jourlin, FR 1752510 (2017)
9. Sauvage-Vincent et al, Opt. Exp. 22(11), (2014)

Administrative information:
Duration: 36 months
Starting date: 01/10/2019
Financial support: ANR - project ANR-18-CE04-0008 “CAPTAIN”
Main supervisor: Dr Jérôme BRUNET – MCF HDR
Position: Axe PHOTON thème MINAMAT
Tel: 04 73 40 72 47 ; Mail: jerome.brunet@uca.fr
Laboratory: Institut Pascal – UMR CNRS 6602
Doctoral School: ED Sciences Pour l’Ingénieur
University: Université Clermont Auvergne
Co-supervisor: PR Yves JOURLIN
Laboratory: Laboratoire Hubert Curien – UMR CNRS 5516
University: Université Jean MONNET – Saint-Etienne