Efficient Monolithic Perovskite/Silicon Tandem Photovoltaics

Tunable bandgaps make halide perovskites promising candidates for developing tandem solar cells (TSCs), a strategy to break the radiative limit of 33.7% for single‐junction solar cells. Combining perovskites with market‐dominant crystalline silicon (c‐Si) is particularly attractive; simple estimates based on the bandgap matching indicate that the efficiency limit in such tandem device is as high as 46%. However, state‐of‐the‐art perovskite/c‐Si TSCs only achieve an efficiency of ~32.5%, implying significant challenges and also rich opportunities. In this review, we start with the operating mechanism and efficiency limit of TSCs, followed by systematical discussions on wide‐bandgap perovskite front cells, interface selective contacts, and electrical interconnection layer, as well as photon management for highly efficient perovskite/c‐Si TSCs. We highlight the challenges in this field and provide our understanding of future research directions toward highly efficient and stable large‐scale wide‐bandgap perovskite front cells for the commercialization of perovskite/c‐Si TSCs.