Brinkmann, K.O.; Becker, T.; Zimmermann, F.; Kreusel, C.; Gahlmann, T.; Theisen, M.; Haeger, T.; Olthof, S.; Tückmantel, C.; Günster, M.; Maschwitz, T.; Göbelsmann, F.; Koch, C.; Hertel, D.; Caprioglio, P.; Peña-Camargo, F.; Perdigón-Toro, L.; Al-Ashouri, A.; Merten, L.; Hinderhofer, A.; Gomell, L.; Zhang, S.; Schreiber, F.; Albrecht, S.; Meerholz, K.; Neher, D.; Stolterfoht, M.; Riedl, T.: Perovskite¿organic tandem solar cells with indium oxide interconnect. Nature 604 (2022), p. 280-286
10.1038/s41586-022-04455-0
Open Access Version
Abstract:
Multijunction solar cells can overcome the fundamental efficiency limits of single-junction devices. The bandgap tunability of metal halide perovskite solar cells renders them attractive for multijunction architectures. Combinations with silicon and copper indium gallium selenide (CIGS), as well as all-perovskite tandem cells, have been reported. Meanwhile, narrow-gap non-fullerene acceptors have unlocked skyrocketing efficiencies for organic solar cells. Organic and perovskite semiconductors are an attractive combination, sharing similar processing technologies. Currently, perovskite–organic tandems show subpar efficiencies and are limited by the low open-circuit voltage (Voc) of wide-gap perovskite cells and losses introduced by the interconnect between the subcells. Here we demonstrate perovskite–organic tandem cells with an efficiency of 24.0 per cent (certified 23.1 per cent) and a high Voc of 2.15 volts. Optimized charge extraction layers afford perovskite subcells with an outstanding combination of high Voc and fill factor. The organic subcells provide a high external quantum efficiency in the near-infrared and, in contrast to paradigmatic concerns about limited photostability of non-fullerene cells, show an outstanding operational stability if excitons are predominantly generated on the non-fullerene acceptor, which is the case in our tandems. The subcells are connected by an ultrathin (approximately 1.5 nanometres) metal-like indium oxide layer with unprecedented low optical/electrical losses. This work sets a milestone for perovskite–organic tandems, which outperform the best p–i–n perovskite single junctions and are on a par with perovskite–CIGS and all-perovskite multijunctions.