Synthesis and Characterization of Lead-Free High-Entropy Relaxor Ceramics for Energy Storage and Electrostrain

Relaxor ferroelectric materials have attracted increasing interest due to their high dielectric permittivity, low dielectric losses, and thermal stability, making them suitable for various applications such as energy-storage capacitors and electrostrictive actuators1-2.
These relaxor materials are characterized by the presence of polar nanoregions (PNRs), in which electric dipoles are correlated at the nanoscale and randomly oriented in the absence of an external electric field..
Recently, the high-entropy oxide (HEO) approach has emerged as a promising strategy for designing high-performance relaxors. The intrinsic chemical disorder, multiple ionic valence states, and strong lattice distortions characteristic of these systems promote the formation of highly dynamic polar nanoregions³. This approach therefore opens new opportunities for optimizing dielectric and electromechanical properties.

GREMAN is a research laboratory on materials, microelectronics, acoustics and nanotechnology of the University of Tours, CNRS and INSA Centre Val de Loire created January 1st 2012 by the merging of several groups located in Tours and Blois, France. Its expertise covers the value chain from materials science up to devices (components, sensors, transducers ...) and their integration. Fields such as electrical energy efficiency, power microelectronics and the use of ultrasonic waves are particularly targeted, for applications in industry, health and nomadic apparatus.

We are looking for a candidate who is passionate about materials and their applications in the field of energy, with:
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A Master’s degree (MSc, second year) or an Engineering degree in Chemistry and Materials Science.
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Experience in ceramic materials and characterization techniques.
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A good command of the English language (written and spoken), as well as strong scientific writing skills.
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Rigor, autonomy, and an interest in working in a research laboratory.