Thermoelectricity in metal-organic perovskites: recycling waste energy heat as electricity

Thermoelectric materials convert thermal and electrical energy, and performant thermoelectric devices could be used to recover waste heat in manufacturing, cogeneration, and heavy transportation - reducing both energy requirements and greenhouse gases' footprint.Solid-state cooldown would also change refrigeration technologies, in both efficiency and maintenance.

Broadly speaking, a materials' breakthrough in thermoelectrics would have an impact on energy efficiency similar to nitride LEDs for lightning technologies.Optimal thermoelectrics need to balance the contrasting requirements of good electrical conductivity and low thermal conductivity; nowadays the best bulk thermoelectric approaching the desired efficiency is SnSe.

However, large-scale production is too expensive, and applications remain limited to niche markets.The goal of this project is to find efficient thermoelectrics in the class of metal-organic single and double halide perovskites.These are intensely studied for their photovoltaic efficiency, thanks also to their good electrical properties; they can be manufactured inexpensively at scale; and their lattice vibrations are very anharmonic and tunable, allowing to engineer low thermal conductivity.Since the overall number of possible compounds is above 500, there is wide chemical tunability of their properties.

However, due to both theoretical and experimental difficulties, thermoelectric efficiency has been investigated only in very few compounds.

Thanks to the unique capabilities I have developed during my PhD to study from first-principles materials with very large anharmonic distortions, I will investigate the full chemical space of these perovskites in the quest for the most efficient thermoelectric.

Success in the project would bring major advantages to the industrial and economic EU ecosystem, but will also cement my leadership in characterizing and designing electrical and thermal properties of far from equilibrium materials.