Ultrathin perovskite solar cell based on Gires-Tournois resonator configuration with 27% theoretical efficiency

Abstract

Ultrathin photovoltaic devices hold significant potential for the efficient conversion of solar energy to electricity, offering the advantages of reduced material consumption and deposition time. The key challenge is to achieve high light absorption in ultra-thin layers while minimizing photocurrent losses. In this study, we introduce a strategy centered on super absorption in planar active layers. We have engineered an ultrathin perovskite solar cell featuring a 45-nm-thick absorption layer that exhibits an average absorptivity of 85 % within the visible light and a theoretical efficiency up to ∼ 27 % under certain conditions. This design employs a straightforward silver-backed mirror to enact an effective light-capture technique based on current perovskite solar cell configurations. The observed boost in visible light absorption is attributable to the potent super absorption of the Gires-Tournois resonator configuration. We further analyzed the impact of the built-in electric field on the recombination rate, noting that the enhancement in efficiency is attributed to the effective extraction of charge carriers. The effects of operating temperature and parasitic resistance on the performance of the device are evaluated. This assessment helps to understand how these factors influence efficiency and stability, providing insights for optimizing device design in practical settings.