Photonic-Structured Perovskite Solar Cells: Detailed Optoelectronic Analysis

Abstract

Recent experimental advances in perovskite solar cell (PSC) technology marked a new era for low-cost, flexible, and high-efficiency photovoltaics (PVs). In contrast, the study of the detailed physical mechanisms governing the optoelectronic properties of PSCs has not been keeping up with these breakthroughs, which have been eclipsing theoretical efforts aimed at a more in-depth understanding of this emerging PV technology. Consequently, this has been hindering the design of the devices from reaching their maximum potential. The present article aims to bridge this gap by using a coupled optical and electrical modeling approach to optimize and rigorously assess the transport properties of selected photonic-structured PSC architectures, with particular attention given to ultrathin (300 nm) perovskite absorbers as they can pronouncedly benefit from the light-trapping effects provided by micro-structuring. The central finding of this study is that photonic-structured ultrathin PSCs benefit from significantly enhanced light in coupling and subsequent photocurrent generation in the absorber layer. This leads to more than 20% increase in the short circuit current in comparison with planar devices. In addition, slight increases in the open-circuit voltage and fill factor can be obtained due to the ultrathin perovskite absorbers, and thus, power conversion efficiencies approaching 30% are possible. Moreover, it was also found that the electrical simulations of complex 3D device geometries can be accurately simplified to 1D, massively benefiting the computational efficiency of these studies.