Functional Materials for Energy and Photonics
Channel: Biblioteca Pós-graduação em Física UFMG
Date: 08/09/2021

Título: Functional Materials for Energy and Photonics

Palestrante: Marina Leite - Department of Materials Science and Engineering, UC Davis

Resumo:

My research group is engaged in fundamental and applied research in emerging materials for energy harvesting and storage, nanophotonics, and optoelectronics. The performance of most photovoltaic devices is still limited by their nanoscale behavior. To reveal how the electrical and optical responses vary at relevant length scales, we acquire nanoscale resolved “photographs” and “movies” of the performance of inhomogeneous materials for photovoltaics, by means of sophisticated nanospectroscopic methods that we have developed. Our measurements provide a tomography of charge carrier generation, recombination, and collection within materials ranging from well-established thin films to emerging perovskites. In particular, we probe the correlation between perovskites’ stability and the chemical changes that occur when the material is exposed to humidity, oxygen, temperature, light, and bias. Our functional imaging platform can be expanded to quantum and low-dimensional materials, as planned for the near future. In the realm of energy storage, the further development of rechargeable, safe batteries requires the understanding of why and how the material is changing upon charging/discharging. Concerning optical materials, we design and probe metallic materials beyond noble metals. We overcome the constraint imposed by the pre-defined dielectric functions of metals by alloying, where we have recently developed a library of their optical properties. Moreover, we recently discovered a platform based on earth-abundant materials for reconfigurable and biodegradable photonics. Our approach enables new materials with on demand optical response for applications ranging from electrocatalysis to color displays.