PhD offer in ultrasonic wave propagation and biobased materials

Ultrasonic energy harvesting has lately been introduced as a promising wireless energy transfer solution to power miniaturized wearable and implantable electronic devices for wireless communication and sensing, remote health monitoring, and ultrasound-induced therapies. However, most current ultrasonic energy harvesters operate using bulky, lead-based piezoelectric materials, which still present major limitations. For instance, they are brittle, inflexible, and contain toxic elements, which limits their wearability and biomedical applications. Moreover, the production and disposal of these inorganic materials pose serious environmental and sustainability challenges.

Plants present a biobased materials’ platform to overcome these challenges due to their piezoelectric behavior. In this project, we aim to design plant-based materials, with enhanced piezoelectricity, for efficient energy harvesting of ultrasonic waves. In order to optimize the electromechanical coupling in these biobased structures, we will exploit the interplay between recently discovered phononic features in plants and existing plant piezoelectricity. In this context, the proposed Ph.D. will focus on identifying phononic features for ultrasonic energy localization in plant-based composite materials and converting plant-based composites into efficient energy harvesters.

As part of this, the Ph.D. student will help implement the necessary tools to:

1) Fabricate and characterize micro-structured cellular membranes made from dehydrated plant scaffolds using soft lithography, optical microscopy, nanometrology (i.e. profilometry, AFM, SEM), and image processing.

2) Measure and analyze the propagation of MHz to GHz ultrasonic waves in the fabricated samples using laser ultrasonics setups and signal processing techniques.

3) Model and evaluate the energy harvesting performance of the designed materials via experimental characterization and numerical modeling of their phononic and piezoelectric behavior, as well as their electromechanical coupling