Revealing the output power potential of bifacial monolithic all-perovskite tandem solar cells

Bifacial monolithic all-perovskite tandem solar cells have the promise of delivering higher output power density by inheriting the advantages of both tandem and bifacial architectures simultaneously. Herein, we demonstrate, for the first time, the bifacial monolithic all-perovskite tandem solar cells and reveal their output power potential. The bifacial tandems are realized by replacing the rear metal electrodes of monofacial tandems with transparent conduction oxide electrodes. Bandgap engineering is deployed to achieve current matching under various rear illumination conditions. The bifacial tandems show a high output power density of 28.51 mW cm −2 under a realistic rear illumination (30 mW cm − 2 ). Further energy yield calculation shows substantial energy yield gain for bifacial tandems compared with the monofacial tandems under various ground albedo for different climatic conditions. This work provides a new device architecture for higher output power for all-perovskite tandem solar cells under real-world conditions.