The functional materials team of the Institute of Electronics and Digital Technologies (CNRS affiliated research unit: IETR, University of Nantes) and MOLTECH Anjou are looking for a postdoctoral researcher to work on an interdisciplinary project (1 year) combining polymer film fabrication and experimental physics.
JOB LOCATION: University of Nantes, France
In the field of ambient mechanical micro-energy harvesting (from µW to mW range), many studies deal with low frequency (<100Hz) vibrations, whose energy is generally harvested with piezoelectric materials, owing to their ability to mechanical-electrical energy conversion and easy integration in task-oriented systems. The objective of the project is to propose an alternative to piezoelectricity by developing flexoelectric polymer films. Flexoelectric effect, which corresponds to the appearance of an electric polarization induced by a strain gradient (i.e. curvature) is a universal effect in all solid dielectrics. However, this coupling is relatively understudied and remains weak in comparison with piezoelectric effect in organic films. The goal is thus to elaborate and characterize all-organic soft films able to withstand large curvatures with sufficiently high flexoelectric coefficients to envisage their potential use as mechanical energy harvesters.
The two project partners (IETR, University of Nantes and MOLTECH Anjou, University of Angers) have recently shown that giant flexoelectric coefficients could be achieved in specific semi-conducting polymers, along with their potentiality for mechanical-electrical energy conversion. However, some features need to be improved. Thus, the successful candidate will be working on the stability of the flexoelectric coupling and the fabrication of self-supported films, in view of significantly increase the subjected strain gradient and so the generated output current. It is also planned to develop semi-conducting/insulating polymer composites and specific electrode patterns to enhance the harvested power density.
The successful candidate must have a PhD in material science, polymer physics or a related field. Experience in electromechanical characterization and cleanroom fabrication would be assets. Good academic performance and a demonstrated knowledge of written and spoken English are required.