Low‐Cost Strategy for High‐Efficiency Bifacial Perovskite/c‐Si Tandem Solar Cells

Many studies have confirmed that the perovskite/crystalline silicon (c‐Si) tandem solar cells (TSCs) can achieve excellent photovoltaic performance far exceeding that of single‐junction solar cells. However, the quite thick c‐Si bottom‐cells have to be used to fully absorb near‐infrared photons, which greatly improves the cost of the TSCs. The bifacial two‐terminal TSCs not only can improve the energy output by introducing rear incident light, but also significantly reduce the Si thickness while maintaining high efficiency. Herein, the photovoltaic performance of bifacial perovskite/c‐Si TSCs under different Si thicknesses, pyramid heights, and albedos have been calculated. It is found that the thickness of the c‐Si sub‐cells can be reduced from the current 250 to 25 μm, and only the albedos need to be increased by 18.6% to cover the absorption loss in the near‐infrared. It is recommended that 100‐μm thick c‐Si is a suitable candidate and optimized the size of the Si pyramids (1.0 μm) to obtain excellent light trapping performance. This work can serve as a guidance for experimental preparation of low‐cost and high‐efficiency bifacial perovskite/c‐Si TSCs.