Thèses

Lundi 23 Novembre 2020 à 14h00.

Conversion of Mechanical Energy into Light. Understanding the phenomenon in the case of phosphor-elastomer composite materials

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Elastico-MechanoLuminescence (EML), which is the phenomenon where luminescence is induced by elastic deformation of solids, has known an increasing interest these last few years. The study of composite materials ZnS:Cu/Mn-PDMS (polydimethylsiloxane) arose. However, the origin of this mechanism is not fully established.
This work discusses the different mechanisms of EML using two approaches. One is to evaluate a model material under stretch condition and analyse its optical response. The other is to synthesize different materials and test their efficiency against different structural and morphological parameters. The conclusions of these results lead to favour triboelectricity as EML mechanism. This point highlights the importance of the surface of the microparticles which helps to provide a better understanding of the phenomenon as to propose a mechanism for activating EML and to establish a model applicable to different materials.
Thanks to this new approach, it is possible to trigger luminescence by friction or separation of surfaces (by tearing), both based on triboelectricity using other matrixes such as epoxy resin and silly putty.

Directeurs de thèse : Christophe Dujardin et Benoît Mahler

Membres du jury :
Anna VEDDA, Philippe SMET, Catherie JOURNET-GAUTIER, Thierry GACOIN, Geneviève CHADEYRON.

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