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 similar to 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.