Thermoelectric devices hold great promise for the future energy landscape. They convert waste heat into usable electricity and can provide on demand cooling or heating. Despite their potential, the low efficiency of thermoelectric devices has limited their adoption. Advances in the properties of materials used in thermoelectric devices are needed to make this promising technology a reality. The PIs will investigate a new family of materials for thermoelectric applications: hybrid metal halide perovskites with organic and inorganic components. Students will receive training in materials science and engineering. This project will impact the materials science and electronics communities and inspire future scientists and engineers dedicated to sustainable energy solutions.
Hybrid metal halide perovskites are low-thermal conductivity materials with clear benefits in practical, solution-processed thermoelectric devices from a performance and cost basis. Yet, little effort has been placed in fabricating thermoelectric devices from perovskite systems. This lack of study and implementation is mainly due to the key challenge in finding a means by which to effectively control the charge carrier concentration and electrical conductivity of the devices through straightforward doping strategies. The conventional approach to doping that is focused on atomic substitution in the lattice does not work for halide perovskites due to charge screening and the defect-tolerant nature of typical perovskite systems. Therefore, a shift in archetype regarding doping in perovskite devices must be had in order to overcome this key challenge. This critical opportunity will be addressed by incorporating radical-containing ligands into the actual perovskite crystal lattice in order to serve as intramolecular dopants for the thermoelectric devices. This project is based on the PIs' prior work in manipulating the optoelectronic properties of perovskite-based devices by incorporating closed-shell organic ligands into the crystal structures of the materials and previous success of using radical-based dopants to enhance the performance of polymer thermoelectric devices. Inclusion of these radical dopants will allow for the ready tuning of the carrier concentrations and electrical and thermal conductivities associated with the semiconducting materials through intramolecular means. This project will enable manipulation of the key structure-property-performance relationships in a novel class of printed electronic materials, and in doing so, demonstrate high-performance devices.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
