Monolithic perovskite/organic tandem solar cells: Developments, prospects, and challenges

Abstract Monolithic perovskite solar cells (PSCs) and small‐bandgap organic photovoltaics (OPVs) integrated perovskite/organic tandem devices and binary perovskite/bulk‐heterojunction (BHJ) devices have recently attracted tremendous attention due to their upgraded light‐harvesting range and theoretical efficiency potential. However, compared with the ideal integrated condition, tandem devices usually exhibit obviously reduced current density (Jsc) and open‐circuit voltage (Voc), which results in compromised power conversion efficiency (PCE). Moreover, the champion PCE of perovskite/organic tandem devices is still lower than that of the best reported single‐junction PSCs. Therefore, relieving their Jsc and Voc losses is vital to develop high‐performance perovskite/organic tandem devices. Besides, several perovskite/BHJ devices are emerging. This paper presents a systematic overview of developing perovskite/organic tandem devices. Particularly, this is the first study to have comprehensively summarized the factors affecting perovskite/organic tandem device efficiency loss, as well as the modulating strategies. Meanwhile, the development of perovskite/BHJ devices is also discussed. Finally, the prospects and development challenges of perovskite/organic tandem devices in the near future are presented