Hybrid interconnecting layers reduce current leakage losses in perovskite/silicon tandems with 81.8% fill factor

To break through the Shockley-Queisser limit of single-junction photovoltaics, monolithic two-terminal (2T) perovskite/silicon tandem solar cells (TSCs) have shown promise in recent years. Self-assembled monolayers (SAMs) as interconnecting layers (ICLs) for efficient perovskite/silicon TSCs are favorable due to their negligible optical and electrical loss. However, the inhomogeneity of SAMs results in defects at the interface between SAMs and transparent conductive oxide (TCO). To solve this issue, in this work, we employ the sputtered nickel oxide (NiO_x) as the seed layer of MeO-2PACz SAMs to build hybrid ICLs in perovskite/silicon TSCs. It is found that the hybrid ICLs of NiO_x/MeO-2PACz significantly reduce current leakage and non-radiative recombination losses by avoiding direct contact between perovskites and TCO. As a result, we can fabricate reproducible and stable monolithic 2T perovskite/silicon TSCs with an efficiency of 28.47% and an impressive fill factor of 81.8%.