Abstract: Organic-inorganic lead halide perovskites have demonstrated exceptional applications in optoelectronic devices, including photodetectors, light-emitting diodes, and solar cells. Such applications stem from their intriguing optoelectronic properties, such as high absorption coefficient, long carrier lifetime, tunable bandgap, and low defect density. In this talk, I will explain why halide perovskites exhibit such exceptional optoelectronic properties, whereas other semiconductors do not. In solar cell applications, I will emphasize two unusual opportunities enabled by metal halide perovskites, including bifacial thin-film solar cells and low-cost thin-film tandem and multi-junction solar cells. Lastly, I will discuss the challenges facing perovskite solar cells, such as large-scale module production, the toxicity of lead, and their vulnerability to moisture, heat, and light. 

Yanfa Yan is an Ohio Research Scholar Endowed Chair and a Distinguished University Professor in the Department of Physics and Astronomy at The University of Toledo. He is also a Faculty Member of the Wright Center for Photovoltaics Innovation and Commercialization.  Previously, he was a Principal Scientist at the National Renewable Energy Laboratory. His expertise includes thin-film solar cell fabrication, defect physics of semiconductors, and nanoscale characterization of microstructures, interfaces, and defects in thin-film photovoltaic materials. He is a Fellow of the American Physical Society.