Towards elusive hybrid perovskite carrier dynamics through ultrafast THz spectroscopy: Influence of quantum confinement and charge transport layers

Abstract

Development of solar cells which are simultaneously cheap, stable, scalable, and highly efficient is crit. to realizing the vision of globally accessible renewable energy dependence. Over the past decade, hybrid org.-inorg. perovskite materials have experienced a meteoric rise in research efforts which continue to demonstrate the promise of perovskite technol. in all these areas. We still lack, however, a detailed understanding of the fundamental charge carrier dynamics and photogenerated charge transport behavior in these materials with respect to quantum confinement and solar cell interfaces. Ultrafast terahertz (THz, or far-IR) spectroscopy provides a time-resolved, non-invasive probe of the collective carrier dynamics and lattice vibrations in semiconductors, both from sub-bandgap and photoexcited absorption as well as from THz emission. We discuss comprehensive THz investigations in benchmark hybrid perovskite systems that will allow for the extn. of crucial material parameters such as carrier mobility, permittivity, photocond., and lattice-coupling to intimately assess the influence of 2D architectures and electron/hole transport layers. Characterization in this manner offers vital insights to guide the rapid development of perovskite solar cells and strengthens our foundational knowledge of hybrid perovskite materials. Furthermore, cohesively optimizing perovskite potential through diverse scientific frontiers is necessary to achieve the revolutionary energy technol. of our future.